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Sample records for microscopy x-ray microanalysis

  1. Scanning electron microscopy and electron probe X-ray microanalysis (SEM-EPMA) of pink teeth

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    Ikeda, N.; Watanabe, G.; Harada, A.; Suzuki, T.

    1988-11-01

    Samples of postmortem pink teeth were investigated by scanning electron microscopy and electron probe X-ray microanalysis. Fracture surfaces of the dentin in pink teeth were noticeably rough and revealed many more smaller dentinal tubules than those of the control white teeth. Electron probe X-ray microanalysis showed that the pink teeth contained iron which seemed to be derived from blood hemoglobin. The present study confirms that under the same circumstance red coloration of teeth may occur more easily in the teeth in which the dentin is less compact and contains more dentinal tubules.

  2. Applications of scanning electron microscopy and X-ray microanalysis in inner ear pathology

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    Anniko, M.; Lim, D.J.; Sobin, A.; Wroblewski, R.

    1985-01-01

    Surface pathology of inner ear structures so far described in detail concern cochlear and vestibular hair cells and the stria vascularis. In man, surgical intervention into the inner ear is very uncommon and when performed is in general with the primary objective of destroying the diseased peripheral end organs. The vast majority of inner ear tissue available for use with scanning electron microscopy (SEM) is therefore obtained from animals. The present paper reviews the progression of surface pathology caused by aminoglycoside antibiotics, acoustic overstimulation and in a guinea pig strain with genetic inner ear disease. The primary site of onset of surface pathology differs, depending on the underlying cause. Advanced surface pathology shows a similar type of morphological degeneration independent of cause. The combination of SEM and energy dispersive X-ray microanalysis (XRMA) of inner ear pathology has as yet been reported in only three studies, all concerning inner ear fluids or otoconia.

  3. Clinical applications of scanning electron microscopy and X-ray microanalysis in dermatology

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    Forslind, B.

    1984-01-01

    Scanning electron microscopy is frequently applied to dermatological problems, as is evident from a review of the recent literature. In this paper, preparation methods and new techniques allowing experimental studies on the integumentary system are emphasized. Quantitative analysis in the electron microscope by use of energy-dispersive X-ray microanalysis (EDX) has become an important accessory technique. EDX can, for instance, be used to study problems involving physiological changes induced in skin by agents causing contact reactions. Recently, it has been shown that treatment with DNCB, chromate and nickel causes changes in elemental distribution in guinea-pig skin. In addition, elemental uptake in the integumentary system and in pathological inclusions in skin can be analyzed.

  4. Cadmium toxicity in perinatal rat hepatocytes: Electron microscopy, X-ray microanalysis, and morphometric analysis

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    Kawahara, A.; Yoshizuka, M.; Hirano, T.; Ohsato, K.; Fujimoto, S. (Univ. of Occupational and Environmental Health, Kitakyushu (Japan))

    1990-10-01

    Effects of cadmium on the fetal and postnatal rat hepatocytes were studied with an electron microscope and an X-ray microanalyzer. Pregnant and lactating Wistar rat dams at 15 and 21 days of pregnancy and at 3 days after delivery received intraperitoneal injections of cadmium sulfate (1 mg/kg body weight) for 3 days. On the day following the last injection, the livers were isolated from the fetal and suckling rats and provided for electron microscopy. The livers from the untreated fetal and newborn rats served as control. Large bile canaliculi, which were formed by five or more hepatocytes, were frequently observed in the cadmium-treated perinatal rat livers. The intercellular space between each adjacent hepatocyte was widened. By X-ray microanalysis, cadmium peaks were preferentially detected out from intramitochondrial granules of the cadmium-treated hepatocytes. By morphometric analysis, the increase both in the mitochondria volume and in the number of intramitochondrial granules was evident in the cadmium-treated hepatocytes when compared to those of control. These data suggest the preferential accumulation of cadmium in mitochondria of the hepatocytes interferes with the morphogenesis of the perinatal rat liver.

  5. Cadmium toxicity to the cornea of pregnant rats: Electron microscopy and x-ray microanalysis

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    Yoshizuka, M.; McCarthy, K.J.; Kaye, G.I.; Fujimoto, S. (Univ. of Occupational and Environmental Health, School of Medicine, Kitakyushu (Japan))

    1990-05-01

    Cadmium toxicity to the cornea of pregnant rats was studied using the electron microscope and x-ray microanalyzer. In in-vivo experiments, severe corneal edema occurred in pregnant dams that received intraperitoneal injections of cadmium sulphate for 4 days during gestation, but not in nonpregnant rats. Prominent swelling of mitochondria and the occurrence of intra- and intercellular vacuoles in the corneal endothelium were observed only in pregnant dams. In in-vitro experiments, electron-dense deposits consisting of cadmium-oxine complexes were preferentially found in swollen mitochondria of the endothelial cells. Cadmium peaks were obtained from these deposits with x-ray microanalysis. These data suggest that the corneal edema observed after administration of cadmium may imply the disturbance of pump function and barrier function of the corneal endothelium due to the primary toxic effects of this metal on mitochondria.

  6. Rigorous quantitative elemental microanalysis by scanning electron microscopy/energy dispersive x-ray spectrometry (SEM/EDS) with spectrum processing by NIST DTSA-II

    Science.gov (United States)

    Newbury, Dale E.; Ritchie, Nicholas W. M.

    2014-09-01

    Quantitative electron-excited x-ray microanalysis by scanning electron microscopy/silicon drift detector energy dispersive x-ray spectrometry (SEM/SDD-EDS) is capable of achieving high accuracy and high precision equivalent to that of the high spectral resolution wavelength dispersive x-ray spectrometer even when severe peak interference occurs. The throughput of the SDD-EDS enables high count spectra to be measured that are stable in calibration and resolution (peak shape) across the full deadtime range. With this high spectral stability, multiple linear least squares peak fitting is successful for separating overlapping peaks and spectral background. Careful specimen preparation is necessary to remove topography on unknowns and standards. The standards-based matrix correction procedure embedded in the NIST DTSA-II software engine returns quantitative results supported by a complete error budget, including estimates of the uncertainties from measurement statistics and from the physical basis of the matrix corrections. NIST DTSA-II is available free for Java-platforms at: http://www.cstl.nist.gov/div837/837.02/epq/dtsa2/index.html).

  7. Characterization of leaf-level particulate matter for an industrial city using electron microscopy and X-ray microanalysis

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    Sgrigna, G., E-mail: gregorio.sgrigna@ibaf.cnr.it [University of Molise (UniMol), Department of Biosciences and Territory, Contrada Fonte Lappone Pesche (Italy); Institute of Agro Environmental and Forest Biology, National Research Council (IBAF–CNR), Via Marconi, 2 Porano & Via Castellino 111, Napoli (Italy); Baldacchini, C., E-mail: chiara.baldacchini@ibaf.cnr.it [Institute of Agro Environmental and Forest Biology, National Research Council (IBAF–CNR), Via Marconi, 2 Porano & Via Castellino 111, Napoli (Italy); Esposito, R., E-mail: raffaela.esposito@ibaf.cnr.it [Institute of Agro Environmental and Forest Biology, National Research Council (IBAF–CNR), Via Marconi, 2 Porano & Via Castellino 111, Napoli (Italy); Calandrelli, R., E-mail: roberto.calandrelli@ibaf.cnr.it [Institute of Agro Environmental and Forest Biology, National Research Council (IBAF–CNR), Via Marconi, 2 Porano & Via Castellino 111, Napoli (Italy); Tiwary, A., E-mail: a.tiwary@soton.ac.uk [Faculty of Engineering and the Environment, University of Southampton, Highfield Campus, Southampton SO17 1BJ (United Kingdom); Calfapietra, C., E-mail: carlo.calfapietra@ibaf.cnr.it [Institute of Agro Environmental and Forest Biology, National Research Council (IBAF–CNR), Via Marconi, 2 Porano & Via Castellino 111, Napoli (Italy); Global Change Research Centre, Academy of Sciences of the Czech Republic, v. v. i., Bělidla 986/4a, 603 00 Brno (Czech Republic)

    2016-04-01

    This study reports application of monitoring and characterization protocol for particulate matter (PM) deposited on tree leaves, using Quercus ilex as a case study species. The study area is located in the industrial city of Terni in central Italy, with high PM concentrations. Four trees were selected as representative of distinct pollution environments based on their proximity to a steel factory and a street. Wash off from leaves onto cellulose filters were characterized using scanning electron microscopy and energy dispersive X-ray spectroscopy, inferring the associations between particle sizes, chemical composition, and sampling location. Modeling of particle size distributions showed a tri-modal fingerprint, with the three modes centered at 0.6 (factory related), 1.2 (urban background), and 2.6 μm (traffic related). Chemical detection identified 23 elements abundant in the PM samples. Principal component analysis recognized iron and copper as source-specific PM markers, attributed mainly to industrial and heavy traffic pollution respectively. Upscaling these results on leaf area basis provided a useful indicator for strategic evaluation of harmful PM pollutants using tree leaves. - Highlights: • Urban tree leaves were used for passive PM{sub 10} monitoring combining SEM and EDX analyses. • Particle mean diameter distributions were modeled by multimode lognormal functions. • Site-specific PM{sub 10} elemental composition was evaluated by principal component analysis. • PM profile (size and composition) was used to distinguish site-specific urban sources. • PM size and relative content of Cu and Fe emerged as possible pollutant source markers.

  8. Scanning electron microscopy and energy-dispersive X-ray microanalysis studies of early dental calculus on resin plates exposed to human oral cavities.

    Science.gov (United States)

    Kodaka, T; Ohohara, Y; Debari, K

    1992-06-01

    Dental calculus formed after 10 days on resin plates, applied to the lingual sides of the mandibular gingival regions in eight human subjects, was investigated by means of scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX). The mineral deposits were mainly divided into three types: A, B, and C. The type A deposits showing an average Ca/P molar ratio of 1.42 were densely packed with fine needle-shaped crystals formed by the intra- and extra-cellular calcification. The type A deposits, probably composed of Ca-deficient apatites and the transitional forms between apatite and octacalcium phosphate (OCP), were observed in all subjects. The type B deposits showing an average Ca/P molar ratio of 0.96 were aggregated with polygonal column, triangular plate-shaped, and rhombohedral crystals. These crystals identified as brushite (CaHPO4-2H2O:dicalcium phosphate dihydrate: DCPD) were found in four subjects. Platelet-shaped crystals of the type C deposits were observed in three subjects. Their Ca/P molar ratio of 1.26 and the crystal shape were similar to those of OCP. Whitlockite crystals were not found although Mg-containing hexagonal disk-like crystals were observed in two subjects.

  9. Essential Heavy Metals in Renal Tumor Tissue and Its Possible Relation to Carcinogenesis: Applying the Scanning Electron Microscopy Coupled with X-Ray Microanalysis Technique

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    Tânia Nogueira

    2015-03-01

    Full Text Available Background: Metals such as copper and zinc are crucial in several vital functions in the human body; the absence of these metals can cause serious illness. When in excess, however, they can have toxic effects which may be associated with carcinogenesis, as is described in the literature. Thus, it is important to realize that without these essential metals in their due proportion, the human body could not maintain its proper metabolic function. Methods: The main goal of this paper was to compare qualitatively and semi-quantitatively the amount of both copper and zinc present in the tumor tissue (tissue from patients who had undergone partial or radical nephrectomy and in the control tissue (which was adjacent to the tumor tissue. This study was carried out using Scanning Electron Microscopy coupled with X-Ray Microanalysis (SEM-XRM. Results: There is a different concentration of copper and zinc in the samples of tumor tissue and controls that were studied. Conclusion: This work complements previously published results about the presence of metals in the human body and their probable influence on carcinogenesis.

  10. Performing elemental microanalysis with high accuracy and high precision by scanning electron microscopy/silicon drift detector energy-dispersive X-ray spectrometry (SEM/SDD-EDS).

    Science.gov (United States)

    Newbury, Dale E; Ritchie, Nicholas W M

    Electron-excited X-ray microanalysis performed in the scanning electron microscope with energy-dispersive X-ray spectrometry (EDS) is a core technique for characterization of the microstructure of materials. The recent advances in EDS performance with the silicon drift detector (SDD) enable accuracy and precision equivalent to that of the high spectral resolution wavelength-dispersive spectrometer employed on the electron probe microanalyzer platform. SDD-EDS throughput, resolution, and stability provide practical operating conditions for measurement of high-count spectra that form the basis for peak fitting procedures that recover the characteristic peak intensities even for elemental combination where severe peak overlaps occur, such PbS, MoS2, BaTiO3, SrWO4, and WSi2. Accurate analyses are also demonstrated for interferences involving large concentration ratios: a major constituent on a minor constituent (Ba at 0.4299 mass fraction on Ti at 0.0180) and a major constituent on a trace constituent (Ba at 0.2194 on Ce at 0.00407; Si at 0.1145 on Ta at 0.0041). Accurate analyses of low atomic number elements, C, N, O, and F, are demonstrated. Measurement of trace constituents with limits of detection below 0.001 mass fraction (1000 ppm) is possible within a practical measurement time of 500 s.

  11. Implications of Polishing Techniques in Quantitative X-Ray Microanalysis

    Science.gov (United States)

    Rémond, Guy; Nockolds, Clive; Phillips, Matthew; Roques-Carmes, Claude

    2002-01-01

    Specimen preparation using abrasives results in surface and subsurface mechanical (stresses, strains), geometrical (roughness), chemical (contaminants, reaction products) and physical modifications (structure, texture, lattice defects). The mechanisms involved in polishing with abrasives are presented to illustrate the effects of surface topography, surface and subsurface composition and induced lattice defects on the accuracy of quantitative x-ray microanalysis of mineral materials with the electron probe microanalyzer (EPMA). PMID:27446758

  12. The effect of primycin on the intracellular monovalent ion and water contents of rat hepatocytes as revealed by energy dispersive X-ray microanalysis and interference microscopy.

    Science.gov (United States)

    Horváth, I; Nagy, I; Lustyik, G; Váradi, G

    1983-01-01

    Using energy-dispersive X-ray microanalytic and interference microscopic techniques, the intracellular concentration of the monovalent ions (Na+, K+, Cl+) as well as the intracytoplasmic and intracellular water contents were studied in normal and adrenalectomized rat hepatocytes with and without primycin treatment. Although primycin influenced significantly only the intracellular potassium content of the adrenalectomized group, it exerted a marked influence on the intranuclear water content in both the normal and adrenalectomized rats. The intranuclear water content increased significantly in the primycin-treated animals. The conclusion is drawn that the increased level of hydration of the nuclear substances reflects a 'decondensation' of the chromatin which on the other hand, may represent the basis for the various effects of primycin on the induction of certain hepatic enzymes.

  13. Examination of Libby, Montana, Fill Material for Background Levels of Amphibole from the Rainy Creek Complex Using Scanning Electron Microscopy and X-Ray Microanalysis

    Science.gov (United States)

    Adams, David T.; Langer, William H.; Hoefen, Todd M.; Van Gosen, Bradley S.; Meeker, Gregory P.

    2010-01-01

    Natural background levels of Libby-type amphibole in the sediment of the Libby valley in Montana have not, up to this point, been determined. The purpose of this report is to provide the preliminary findings of a study designed by both the U.S. Geological Survey and the U.S. Environmental Protection Agency and performed by the U.S. Geological Survey. The study worked to constrain the natural background levels of fibrous amphiboles potentially derived from the nearby Rainy Creek Complex. The material selected for this study was sampled from three localities, two of which are active open-pit sand and gravel mines. Seventy samples were collected in total and examined using a scanning electron microscope equipped with an energy dispersive x-ray spectrometer. All samples contained varying amounts of feldspars, ilmenite, magnetite, quartz, clay minerals, pyroxene minerals, and non-fibrous amphiboles such as tremolite, actinolite, and magnesiohornblende. Of the 70 samples collected, only three had detectable levels of fibrous amphiboles compatible with those found in the rainy creek complex. The maximum concentration, identified here, of the amphiboles potentially from the Rainy Creek Complex is 0.083 percent by weight.

  14. X-ray Fourier ptychographic microscopy

    CERN Document Server

    Simons, H; Guigay, J P; Detlefs, C

    2016-01-01

    Following the recent developement of Fourier ptychographic microscopy (FPM) in the visible range by Zheng et al. (2013), we propose an adaptation for hard x-rays. FPM employs ptychographic reconstruction to merge a series of low-resolution, wide field of view images into a high-resolution image. In the x-ray range this opens the possibility to overcome the limited numerical aperture of existing x-ray lenses. Furthermore, digital wave front correction (DWC) may be used to charaterize and correct lens imperfections. Given the diffraction limit achievable with x-ray lenses (below 100 nm), x-ray Fourier ptychographic microscopy (XFPM) should be able to reach resolutions in the 10 nm range.

  15. Spatial Resolution and Detectability Limits in Thin-Film X-Ray Microanalysis

    Science.gov (United States)

    Goldstein, J. I.; Lyman, C. E.; Zhang, Jing

    1990-01-01

    The major advantages of performing x-ray microanalysis in the analytical electron microscope (AEM) are the high compositional spatial resolution and the elemental analysis sensitivity. Unfortunately, there is usually a trade-off between these two advantages. This paper discusses the factors involved in the optimization of both spatial resolution and sensitivity during x-ray microanalysis and shows the results of such optimization experiments for several AEM instruments.

  16. Laboratory astrophysics and microanalysis with NTD-germanium-based X-ray microcalorimeters

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    Silver, E.; Schnopper, H.; Bandler, S.; Murray, S.; Madden, N.; Landis, D.; Beeman, J.; Haller, E.; Barbera, M.; Tucker, G.; Gillaspy, J.; Takacs, E.; Porto, J

    2000-04-07

    With the ability to create cosmic plasma conditions in the laboratory it is possible to investigate the dependencies of key diagnostic X-ray lines on density, temperature, and excitation conditions that exist in astrophysical sources with X-ray optics and a high-resolution X-ray microcalorimeter. The same instrumentation can be coupled to scanning electron microscopes or X-ray fluorescence probes to analyze the elemental and chemical composition of electronic, biological, geological and particulate materials. We describe how our microcalorimeter and X-ray optics provide significantly improved capabilities for laboratory astrophysics and microanalysis.

  17. Identification of inorganic dust particles in bronchoalveolar lavage macrophages by energy dispersive x-ray microanalysis.

    Science.gov (United States)

    Johnson, N F; Haslam, P L; Dewar, A; Newman-Taylor, A J; Turner-Warwick, M

    1986-01-01

    This study shows that energy dispersive x-ray microprobe analysis to identify and quantify intracellular particles in macrophages obtained by the minimally invasive method of bronchoalveolar lavage (BAL) can detect inorganic dust exposures of many different kinds. Bronchoalveolar lavage macrophages from 22 patients have been examined. Twelve patients had occupational exposure to asbestos, talc, silica, hard metal or printing ink, while 10 had no known history of dust exposure. X-ray microprobe analysis identified particles which related to the known exposures, superimposed on a background of other particles related to smoking (kaolinite and mica) or to the general environment (silicon, titanium, and iron). The particle identification provided useful objective confirmation of the known exposures, except for silica, which could not be distinguished from the general background levels. X-ray microanalysis using BAL macrophages can be helpful for clarification of mixed dust exposures, to identify particles when light microscopy indicates retained dust in patients with no known history of exposure, and to monitor retained particles after removal from exposure.

  18. X-ray microscopy of human malaria

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    Magowan, C.; Brown, J.T.; Mohandas, N.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Associations between intracellular organisms and host cells are complex and particularly difficult to examine. X-ray microscopy provides transmission images of subcellular structures in intact cells at resolutions superior to available methodologies. The spatial resolution is 50-60nm with a 1 micron depth of focus, superior to anything achievable with light microscopy. Image contrast is generated by differences in photoelectric absorption by the atoms in different areas (i.e. subcellular structures) throughout the full thickness of the sample. Absorption due to carbon dominates among all the elements in the sample at 2.4 nm x-ray wavelength. Thus images show features or structures, in a way not usually seen by other types of microscopy. The authors used soft x-ray microscopy to investigate structural development of Plasmodium falciparum malaria parasites in normal and genetically abnormal erythrocytes, and in infected erythrocytes treated with compounds that have anti-malarial effects. X-ray microscopy showed newly elaborated structures in the cytosol of unstained, intact erythrocytes, redistribution of mass (carbon) in infected erythrocytes, and aberrant parasite morphology. Better understanding of the process of intracellular parasite maturation and the interactions between the parasite and its host erythrocyte can help define new approaches to the control of this deadly disease.

  19. Backscattered electron imaging and windowless energy dispersive x-ray microanalysis: a new technique for gallstone analysis

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    Kaufman, H.S.; Lillemoe, K.D.; Magnuson, T.H.; Frasca, P.; Pitt, H.A. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

    1990-12-01

    Scanning electron microscopy with or without conventional energy dispersive x-ray microanalysis is currently used to identify gallstone microstructure and inorganic composition. Organic calcium salts are among many biliary constituents thought to have a role in gallstone nidation and growth. However, current analytical techniques which identify these salts are destructive and compromise gallstone microstructural data. We have developed a new technique for gallstone analysis which provides simultaneous structural and compositional identification of calcium salts within gallstones. Backscattered electron imaging is used to localize calcium within cholesterol at minimum concentrations of 0.01%. Windowless energy dispersive x-ray microanalysis produces elemental spectra of gallstone calcium salts which are qualitatively and quantitatively different. These combined techniques provide simultaneous structural and compositional information obtained from intact gallstone cross-sections and have been used to identify calcium salts in gallstones obtained at cholecystectomy from 106 patients.

  20. Contact x-ray microscopy using Asterix

    Science.gov (United States)

    Conti, Aldo; Batani, Dimitri; Botto, Cesare; Masini, Alessandra; Bernardinello, A.; Bortolotto, Fulvia; Moret, M.; Poletti, G.; Piccoli, S.; Cotelli, F.; Lora Lamia Donin, C.; Stead, Anthony D.; Marranca, A.; Eidmann, Klaus; Flora, Francesco; Palladino, Libero; Reale, Lucia

    1997-10-01

    The use of a high energy laser source for soft x-ray contact microscopy is discussed. Several different targets were used and their emission spectra compared. The x-ray emission, inside and outside the Water Window, was characterized in detail by means of many diagnostics, including pin hole and streak cameras. Up to 12 samples holders per shot were exposed thanks to the large x-ray flux and the geometry of the interaction chamber. Images of several biological samples were obtained, including Chlamydomonas and Crethidia green algae, fish and boar sperms and Saccharomyces Cerevisiae yeast cells. A 50 nm resolution was reached on the images of boar sperm. Original information concerning the density of inner structures of Crethidia green algae were obtained.

  1. A combination of a SEM technique and X-ray microanalysis for studying the spore germination process of Clostridium tyrobutyricum.

    Science.gov (United States)

    Bassi, Daniela; Cappa, Fabrizio; Cocconcelli, Pier Sandro

    2009-06-01

    Clostridium tyrobutyricum is an anaerobic bacterium responsible for late blowing defects during cheese ripening and it is of scientific interest for biological hydrogen production. A scanning electron microscopy (SEM) coating technique and X-ray microanalysis were developed to analyze the architecture and chemical composition of spores upon germination in response to environmental changes. In addition, we investigated the effects of different compounds on this process. Agents and environmental conditions inducing germination were characterized monitoring changes in optical density (OD). Among all tested conditions, the greatest drop in OD(625) (57.4%) was obtained when spores were incubated in l-alanine/l-lactate buffer, pH 4.6. In addition, a carbon-coating SEM technique and X-ray microanalysis were used to observe the architecture of spores and to examine calcium dipicolinate release. Conditions inducing C. tyrobutyricum spore germination were identified and SEM X-ray microanalysis clearly distinguished germinating from dormant spores. We confirmed that calcium dipicolinate release is one of the first events occurring. These microscopy methods could be considered sensitive tools for evaluating morphological and chemical changes in spores of C. tyrobutyricum during the initial phase of germination. Information gathered from this work may provide new data for further research on germination.

  2. Electron-Excited X-Ray Microanalysis at Low Beam Energy: Almost Always an Adventure!

    Science.gov (United States)

    Newbury, Dale E; Ritchie, Nicholas W M

    2016-08-01

    Scanning electron microscopy with energy-dispersive spectrometry has been applied to the analysis of various materials at low-incident beam energies, E 0≤5 keV, using peak fitting and following the measured standards/matrix corrections protocol embedded in the National Institute of Standards and Technology Desktop Spectrum Analyzer-II analytical software engine. Low beam energy analysis provides improved spatial resolution laterally and in-depth. The lower beam energy restricts the atomic shells that can be ionized, reducing the number of X-ray peak families available to the analyst. At E 0=5 keV, all elements of the periodic table except H and He can be measured. As the beam energy is reduced below 5 keV, elements become inaccessible due to lack of excitation of useful characteristic X-ray peaks. The shallow sampling depth of low beam energy microanalysis makes the technique more sensitive to surface compositional modification due to formation of oxides and other reaction layers. Accurate and precise analysis is possible with the use of appropriate standards and by accumulating high count spectra of unknowns and standards (>1 million counts integrated from 0.1 keV to E 0).

  3. Use of X-ray microanalysis for study of cation distribution in potassium deficient pumpkin roots

    Directory of Open Access Journals (Sweden)

    Natalia Burmistrova

    2014-01-01

    Full Text Available Ice slices of root tissues were investigated by X-ray microanalysis. It is shown that the cytoplasm of the meristematic and differentiated cells of potassium dificiest roots maintains a high potassium level. The vacuoles of various root cells loose more K and accumulate more Na and Mg than does the cytoplasm.

  4. Improved vacuum evaporation unit for beryllium coating for biological X-ray microanalysis.

    Science.gov (United States)

    Marshall, A T; Carde, D; Kent, M

    1985-09-01

    An improved vacuum evaporator is described for coating frozen-hydrated biological samples with beryllium for X-ray microanalysis. The evaporator permits repeated coatings without bringing the main chamber to atmospheric pressure and ambient temperature. The use of a glass sleeve in the evaporation chamber facilitates cleaning.

  5. Measurement of total calcium in neurons by electron probe X-ray microanalysis.

    Science.gov (United States)

    Pivovarova, Natalia B; Andrews, S Brian

    2013-11-20

    In this article the tools, techniques, and instruments appropriate for quantitative measurements of intracellular elemental content using the technique known as electron probe microanalysis (EPMA) are described. Intramitochondrial calcium is a particular focus because of the critical role that mitochondrial calcium overload plays in neurodegenerative diseases. The method is based on the analysis of X-rays generated in an electron microscope (EM) by interaction of an electron beam with the specimen. In order to maintain the native distribution of diffusible elements in electron microscopy specimens, EPMA requires "cryofixation" of tissue followed by the preparation of ultrathin cryosections. Rapid freezing of cultured cells or organotypic slice cultures is carried out by plunge freezing in liquid ethane or by slam freezing against a cold metal block, respectively. Cryosections nominally 80 nm thick are cut dry with a diamond knife at ca. -160 °C, mounted on carbon/pioloform-coated copper grids, and cryotransferred into a cryo-EM using a specialized cryospecimen holder. After visual survey and location mapping at ≤-160 °C and low electron dose, frozen-hydrated cryosections are freeze-dried at -100 °C for ~30 min. Organelle-level images of dried cryosections are recorded, also at low dose, by means of a slow-scan CCD camera and subcellular regions of interest selected for analysis. X-rays emitted from ROIs by a stationary, focused, high-intensity electron probe are collected by an energy-dispersive X-ray (EDX) spectrometer, processed by associated electronics, and presented as an X-ray spectrum, that is, a plot of X-ray intensity vs. energy. Additional software facilitates: 1) identification of elemental components by their "characteristic" peak energies and fingerprint; and 2) quantitative analysis by extraction of peak areas/background. This paper concludes with two examples that illustrate typical EPMA applications, one in which mitochondrial calcium analysis

  6. Development of a quantification method for x-ray microanalysis with an electron microscope

    Science.gov (United States)

    Horny, Paula

    The overview of the history of quantitative x-ray microanalysis shows the efficiency of the use of standards to achieve the most reliable quantification. State-of-the-art cold field emission gun scanning electron microscopes offer excellent resolution but lack a sufficient level of beam current stability essential for reliable quantitative microanalysis. The purpose of this work is to develop a new method for quantitative x-ray microanalysis adapted to unstable beam current conditions. In the Cliff and Lorimer method, which was developed for the analytical transmission electron microscope, the composition was calculated from the ratio of the characteristic x-ray intensities of two elements in the same spectrum. In this work, this ratio method is applied to bulk specimens in a scanning electron microscope (SEM). In order to reduce the amplitude of error propagation, the proposed ratio for SEM quantitative microanalysis is the intensity of a x-ray divided by the sum of intensities of one or more characteristic lines of each of tire elements found in the specimen. Moreover, the calculated x-ray intensities are corrected for the effects of absorption, fluorescence and Coster-Kronig yields, and other physical factors normally considered in microbeam analysis. Uncertainties in physical parameters and models, clue to the lack of exhaustive measurements as well as their scattering, revealed by a disaggrement between the measured and calculated ratios, are minimized by the use of a calibration factor inserted into the ratio. This calibration factor is determined using a standard for a given element. It can be used as often as needed and allows for the correction of uncertainties in the x-ray detector efficiency. In order to quantify the specimen, the measured experimental ratio is compared to a simulated ratio with the appropriate calibration factor. The composition is interpolated from the theoretical ratio curves. Two methods of calculation of emitted x-ray intensity are

  7. Scanning electron microscopy and X-ray spectroscopy applied to mycelial phase of sporothrix schenckii

    Directory of Open Access Journals (Sweden)

    M. Thibaut

    1975-04-01

    Full Text Available Scanning electron microscopy applied to the mycelial phase of Sporothrix schenckii shows a matted mycelium with conidia of a regular pattern. X-Ray microanalysis applied in energy dispersive spectroscopy and also in wavelength dispersive spectroscopy reveals the presence of several elements of Mendeleef's classification.

  8. Dentin desensitizing agents: SEM and X-ray microanalysis assessment.

    Science.gov (United States)

    Jain, P; Vargas, M A; Denehy, G E; Boyer, D B

    1997-02-01

    To evaluate the effect of four proprietary dentin desensitizing agents on dentin tubular occlusion, chemical composition changes on the dentin surface, and the effect of saliva and toothbrushing on these agents. Fifty dentin discs, obtained from 50 freshly extracted human premolar and molar teeth were used in this study. These were divided into five groups of 10 discs each. Five discs from each group were treated with the desensitizing agents, viewed under the SEM and subjected to energy dispersive X-ray analysis. The other five discs were treated with the desensitizing agents, immersed in artificial saliva, subjected to simulated toothbrushing equivalent to 3 weeks of normal brushing and viewed under the SEM. The agents studied were Sensodyne Dentin Desensitizer, Therma-Trol Desensitizer Gel, Gluma Desensitizer and All-Bond DS. The Kruskal-Wallis test followed by the Wilcoxon signed-rank test showed that Sensodyne Dentin Desensitizer exhibited the greatest amount of tubular occlusion among the unbrushed samples, followed by Therma-Trol Desensitizer Gel, Gluma Desensitizer and All-Bond DS (P Sensodyne Dentin Desensitizer treated samples.

  9. Structural and elemental X-ray microanalysis with synchrotron radiation in confocal geometry

    Energy Technology Data Exchange (ETDEWEB)

    Sosa, Carlos M. [IFEG-CONICET, (X5016LAE) Ciudad Universitaria, Córdoba (Argentina); Sánchez, H. Jorge [IFEG-CONICET, (X5016LAE) Ciudad Universitaria, Córdoba (Argentina); FAMAF, Universidad Nacional de Córdoba, (X5016LAE) Ciudad Universitaria, Córdoba (Argentina); Pérez, Carlos A. [Laboratório Nacional de Luz Síncrotron – LNLS, POB 6192, 13084-971 Campinas, SP (Brazil); Perez, Roberto D., E-mail: danperez@famaf.unc.edu.ar [IFEG-CONICET, (X5016LAE) Ciudad Universitaria, Córdoba (Argentina); FAMAF, Universidad Nacional de Córdoba, (X5016LAE) Ciudad Universitaria, Córdoba (Argentina)

    2014-01-15

    A spectrometer for 3D structural and multielemental X-ray microanalysis with synchrotron radiation is presented in this work. It is based on the combination of the energy dispersive X-ray fluorescence and diffraction with polycapillary optics. The 3D spatial resolution was achieved by the superposition of the foci of two lenses arranged in confocal geometry. The parameters that affect the performance of the spectrometer were study in detail giving rise to a simplified calibration method for depth profile analysis. Two specific examples were included to illustrate the use of the spectrometer in order to identify their possible application fields.

  10. Investigation of soil mineral component in the Baikal Region by X-ray electron probe microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Belozerova, Olga Uu., E-mail: obel@igc.irk.r [Vinogradov Institute of Geochemistry, Siberian Branch, Russian Academy of Sciences, Favorky St., 1 A, 664033 Irkutsk (Russian Federation)

    2009-11-15

    The procedure of X-ray electron probe microanalysis (EPMA) has been developed for the investigation of soil mineral component. In terms of reproducibility and accuracy, the suggested EPMA procedure satisfies the requirements of analysis of the second category. The phase and chemical composition of soil mineral component were investigated by X-ray electron probe microanalysis with the aim of environmental pollution estimation in Lake Baikal Region. The investigations of soil mineral component by EPMA from regions with various man-caused loading degrees allow identification of basic pollution sources and their influence on the environment and estimation of anthropogenic accumulation in clear background regions and regions with high man-caused loading degree.

  11. SEM and X-ray microanalysis of human prostatic calculi

    Energy Technology Data Exchange (ETDEWEB)

    Vilches, J.; Lopez, A.; De Palacio, L.; Munoz, C.; Gomez, J.

    1982-02-01

    Calculi removed from human prostates affected with nodular hyperplasia were analyzed with scanning electron microscopy and EDAX system. The general spectrum was made up of Na, Al, Mg, S, P, Ca and Zn. Two types of stone were identified morphostructurally and microanalytically: calculi type I of nodular surface with high peaks of S, and calculi type II polyfaceted with high peaks of P and Ca. Their formation from corpora amylacea and/or exogenous constituents is discussed. The superficial deposit of Zn suggests its incorporation from the prostatic liquid and does not seem to play an important role in the genesis.

  12. Biological X-ray Microanalysis: The Past, Present Practices, and Future Prospects.

    Science.gov (United States)

    Echlin, Patrick

    2001-03-01

    Abrief description is given of the events surrounding the development of biological X-ray microanalysis during the last 30 years, with particular emphasis on the contribution made by research workers in Cambridge, UK. There then follows a broad review of some applications of biological X-ray microanalysis. A more detailed consideration is given to the main thrust of current procedures and applications that are, for convenience, considered as four different kinds of samples. Thin frozen dried sections which are analyzed at ambient temperatures in a transmission electron microscope (TEM); semithin frozen dried sections which are analyzed at low temperature in a scanning transmission electron microscope (STEM); thick frozen hydrated sections which are analyzed at low temperature in a scanning electron microscope (SEM), and bulk samples which are analyzed at low temperature in the same type of instrument. A brief outline is given of the advantages and disadvantages of performing low-voltage, low-temperature X-ray microanalysis on frozen hydrated bulk biological material. The article concludes with a consideration of alternative approaches to in situ analysis using either high-energy beams or visible and near-visible photons.

  13. Cryotomography x-ray microscopy state

    Science.gov (United States)

    Le Gros, Mark; Larabell, Carolyn A.

    2010-10-26

    An x-ray microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an x-ray microscope. A heat exchanger assembly provides cooled gas to a sample during x-ray microscopic imaging.

  14. Evaluation of X-ray microanalysis for characterization of dental enamel.

    Science.gov (United States)

    Melin, Lisa; Norén, Jörgen G; Taube, Fabian; Cornell, David H

    2014-02-01

    Elemental analysis of dental hard tissues is of importance. The aim of this study is to evaluate X-ray microanalysis (XRMA) of bovine enamel in a scanning electron microscope (SEM) with different coatings. The buccal surface of bovine incisors was polished flat, one-third was coated with carbon, one-third with gold, leaving one-third uncoated for XRMA in an SEM equipped with an energy-dispersive microanalysis system. The elements oxygen, sodium, magnesium, phosphorous, chlorine, potassium, and calcium were analyzed using their respective characteristic K X-ray series. Comparisons were made with analyses of glass produced by fusion of the bovine enamel, showing that oxygen analyses using the K X-ray series are reliable and preferable to calculating oxygen by stoichiometry for natural enamel. For the gold-coated and uncoated analyses, carbon was also measured using the K X-ray series. Small area Analyses in small areas (80 × 80 μm) in variable pressure-SEM mode with low vacuum (20 Pa), without any coating, midway between 40 μm wide gold lines 140 μm apart to avoid build-up of electrostatic charge is the preferred method, especially if carbon is included in the analysis. The analyses of bovine enamel are sufficiently reproducible to be regarded as quantitative for all elements except carbon.

  15. X-ray holographic microscopy: Improved images of zymogen granules

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, C.; Howells, M.; Kirz, J.; McQuaid, K.; Rothman, S.

    1988-10-01

    Soft x-ray holography has long been considered as a technique for x-ray microscopy. It has been only recently, however, that sub-micron resolution has been obtained in x-ray holography. This paper will concentrate on recent progress we have made in obtaining reconstructed images of improved quality. 15 refs., 6 figs.

  16. Transmission electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1993-01-01

    "Transmission Electron Microscopy" presents the theory of image and contrastformation, and the analytical modes in transmission electron microscopy Theprinciples of particle and wave optics of electrons are described Electron-specimen interactions are discussed for evaluating the theory of scattering and phase contrast Also analysed are the kinetical and dynamical theories of electron diffraction and their applications for crystal-structure determination and imaging of lattices and their defects X-ray microanalysis and electron energy-loss spectroscopy are treated as analytical methods The third edition includes a brief discussionof Schottky emission guns, some clarification of minor details, and references to the recent literature

  17. Transmission electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1989-01-01

    The aim of this book is to present the theory of image and contrast formation and the analytical modes in transmission electron microscopy The principles of particle and wave optics of electrons are described Electron-specimen interactions are discussed for evaluating the theory of scattering and phase contrast Also discussed are the kinematical and dynamical theories of electron diffraction and their applications for crystal structure determination and imaging of lattice defects X-ray microanalysis and energy-loss spectroscopy are treated as analytical methods The second edition includes discussion of recent progress, especially in the areas of energy-loss spectroscopy, crystal-lattice imaging and reflection electron microscopy

  18. Dark field X-ray microscopy for studies of recrystallization

    DEFF Research Database (Denmark)

    Ahl, Sonja Rosenlund; Simons, Hugh; Jakobsen, Anders Clemen;

    2015-01-01

    We present the recently developed technique of Dark Field X-Ray Microscopy that utilizes the diffraction of hard X-rays from individual grains or subgrains at the (sub)micrometre- scale embedded within mm-sized samples. By magnifying the diffracted signal, 3D mapping of orientations and strains i...... external influences. The capabilities of Dark Field X- Ray Microscopy are illustrated by examples from an ongoing study of recrystallization of 50% cold-rolled Al1050 specimens....

  19. HERMES: a soft X-ray beamline dedicated to X-ray microscopy.

    Science.gov (United States)

    Belkhou, Rachid; Stanescu, Stefan; Swaraj, Sufal; Besson, Adrien; Ledoux, Milena; Hajlaoui, Mahdi; Dalle, Didier

    2015-07-01

    The HERMES beamline (High Efficiency and Resolution beamline dedicated to X-ray Microscopy and Electron Spectroscopy), built at Synchrotron SOLEIL (Saint-Auban, France), is dedicated to soft X-ray microscopy. The beamline combines two complementary microscopy methods: XPEEM (X-ray Photo Emitted Electron Microscopy) and STXM (Scanning Transmission X-ray Microscopy) with an aim to reach spatial resolution below 20 nm and to fully exploit the local spectroscopic capabilities of the two microscopes. The availability of the two methods within the same beamline enables the users to select the appropriate approach to study their specific case in terms of sample environment, spectroscopy methods, probing depth etc. In this paper a general description of the beamline and its design are presented. The performance and specifications of the beamline will be reviewed in detail. Moreover, the article is aiming to demonstrate how the beamline performances have been specifically optimized to fulfill the specific requirements of a soft X-ray microscopy beamline in terms of flux, resolution, beam size etc. Special attention has been dedicated to overcome some limiting and hindering problems that are usually encountered on soft X-ray beamlines such as carbon contamination, thermal stability and spectral purity.

  20. Practical applications of energy dispersive X-ray microanalysis in diagnostic oral pathology

    Energy Technology Data Exchange (ETDEWEB)

    Daley, T.D.; Gibson, D. (Univ. of Western Ontario, London (Canada))

    1990-03-01

    Energy dispersive X-ray microanalysis is a powerful tool that can reveal the presence and relative quantities of elements in minute particles in biologic materials. Although this technique has been used in some aspects of dental research, it has rarely been applied to diagnostic oral pathology. The purpose of this paper is to inform practicing dentists and oral specialists about the diagnostic potential of this procedure by presenting three case reports. The first case involved the identification of flakes of a metallic material claimed by a 14-year-old girl to appear periodically between her mandibular molars. In the second case, a periodontist was spared a lawsuit when a freely mobile mass in the antrum of his patient was found to be a calcium-phosphorus compound not related to the periodontal packing that had been used. The third case involved the differential diagnosis of amalgam tattoo and graphite tattoo in a pigmented lesion of the hard palate mucosa. The results of the analyses were significant and indicate a role for this technique in the assessment of selected cases. Potential for wider use of energy dispersive X-ray microanalysis in diagnostic oral pathology exists as research progresses.

  1. Spatial resolution of electron probe X-ray microanalysis on sections of organic (biological) material

    Energy Technology Data Exchange (ETDEWEB)

    Krefting, E.-R.; Felsmann, M.; Recker, A.; Feja, B.; Hoehling, H.J.; Reichelt, R. [Institut fuer Medizinische Physik und Biophysik, Westfaelische Wilhelms-Universitaet, Robert-Koch-Str. 31, 48149 Muenster (Germany); Reimer, L. [Physikalisches Institut, Westfaelische Wilhelms-Universitaet, Wilhelm-Klm-Str. 10, 48149 Muenster (Germany)

    1999-05-01

    A locally enhanced element concentration influences the result of an X-ray microanalysis at a neighbouring position. This influence was investigated for the first time systematically in organic (biological) material using sections of epoxy resin (thickness 0.5-2.5 {mu}m) containing a layer of pure gold. Wavelength and energy dispersive spectrometers were applied to analyse the X-rays generated by 15-35 keV electrons. Characteristic X-rays could be detected up to distances of several {mu}m from the gold layer. For example, for a 2.4 {mu}m thick section and 35 keV electrons the measured apparent gold concentration was above 0.1% (weight% per dry mass) at a distance of 10 {mu}m. Thus, the lateral resolution may be not better than a multiple of the section thickness. The apparent gold concentration at a given distance is proportional to the specimen thickness and increases with increasing electron energy. Monte Carlo simulations confirm the experimental results. The influence of a local enrichment depends on the particular specimen properties (e.g. thickness, density, mean atomic number), the electron energy, and the geometry of the detector with respect to the specimen. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. PREFACE: 22nd International Congress on X-Ray Optics and Microanalysis

    Science.gov (United States)

    Falkenberg, Gerald; Schroer, Christian G.

    2014-04-01

    ICXOM22 The 22nd edition of the International Congress on X-ray Optics and Microanalysis (ICXOM 22) was held from 2-6 September 2013, in Hamburg, Germany. The congress was organized by scientists from DESY in collaboration with TU Dresden and Helmholtz-Zentrum Geesthacht, who also formed the scientific advisory board. The congress was hosted in the historical lecture hall building of the University of Hamburg located in the city center. ICXOM22 was attended by about 210 registered participants, including 67 students, and was open for listeners. The attendance was split between 26 countries (Germany 120, rest of Europe 57, America 20, Asia 8, Australia 6). The ICXOM series is a forum for the discussion of new developments in instrumentation, methods and applications in the fields of micro- and nano-analysis by means of X-ray beams. Following the trend of the last 10 years, the conference focusses more and more on synchrotron radiation rather than X-ray laboratory sources. Besides micro-beam X-ray fluorescence and absorption spectroscopy, different methods based on diffraction and full-field imaging were covered. Newly introduced to the ICXOM series was scanning coherent X-ray diffraction imaging, which was shown to evolve into a mature method for the imaging of nanostructures, defects and strain fields. New developments on fast X-ray detectors were discussed (Lambda, Maia) and advances in X-ray optics — like the generation of a sub 5nm point focus by Multilayer Zone plates — were presented. Talks on micro- and nano-analysis applications were distributed in special sessions on bio-imaging, Earth and environmental sciences, and Cultural heritage. The congress featured nine keynote and ten plenary talks, 56 talks in 14 parallel sessions and about 120 posters in three afternoon sessions. Seventeen commercial exhibitors exposed related X-ray instrumentation products, and two luncheon seminars on detector electronics were given. This allowed us to keep the student

  3. X-ray and electron microscopy of actinide materials.

    Science.gov (United States)

    Moore, Kevin T

    2010-06-01

    Actinide materials demonstrate a wide variety of interesting physical properties in both bulk and nanoscale form. To better understand these materials, a broad array of microscopy techniques have been employed, including transmission electron microscopy (TEM), electron energy-loss spectroscopy (EELS), energy dispersive X-ray spectroscopy (EDXS), high-angle annular dark-field imaging (HAADF), scanning electron microscopy (SEM), wavelength dispersive X-ray spectroscopy (WDXS), electron back scattered diffraction (EBSD), scanning tunneling microscopy (STM), atomic force microscopy (AFM), and scanning transmission X-ray microscopy (STXM). Here these techniques will be reviewed, highlighting advances made in the physics, materials science, chemistry, and biology of actinide materials through microscopy. Construction of a spin-polarized TEM will be discussed, considering its potential for examining the nanoscale magnetic structure of actinides as well as broader materials and devices, such as those for computational magnetic memory. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Progress in high-resolution x-ray holographic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, C.; Kirz, J.; Howells, M.; McQuaid, K.; Rothman, S.; Feder, R.; Sayre, D.

    1987-07-01

    Among the various types of x-ray microscopes that have been demonstrated, the holographic microscope has had the largest gap between promise and performance. The difficulties of fabricating x-ray optical elements have led some to view holography as the most attractive method for obtaining the ultimate in high resolution x-ray micrographs; however, we know of no investigations prior to 1987 that clearly demonstrated submicron resolution in reconstructed images. Previous efforts suffered from problems such as limited resolution and dynamic range in the recording media, low coherent x-ray flux, and aberrations and diffraction limits in visible light reconstruction. We have addressed the recording limitations through the use of an undulator x-ray source and high-resolution photoresist recording media. For improved results in the readout and reconstruction steps, we have employed metal shadowing and transmission electron microscopy, along with numerical reconstruction techniques. We believe that this approach will allow holography to emerge as a practical method of high-resolution x-ray microscopy. 30 refs., 4 figs.

  5. X-ray absorption microscopy of aqueous samples

    Science.gov (United States)

    Frazer, Brad; Gilbert, Benjamin; De Stasio, Gelsomina

    2002-03-01

    X-ray photoelectron emission microscopy (X-PEEM) is used for numerous applications in surface microchemical analysis of material science and biological specimens. We have reconfigured the MEPHISTO X-PEEM instrument that is installed at the University of Wisconsin Synchrotron Radiation Center to measure true x-ray transmission spectra by converting transmitted photons to photoelectrons via a thin photocathode layer of gold. We have also developed a method by which to introduce aqueous samples into ultrahigh vacuum. Hence x-ray spectroscopy can be performed on biologically relevant elements (such as K, Ca, etc.) in a physiological environment, i.e., in solution. More important, when coupled with X-PEEM imaging this technique may offer the unique and exciting possibility of studying living cells. We present initial x-ray absorption spectra of solutions of aqueous ionic and chelated Ca, with the aim of distinguishing bound and free ionic calcium in vivo.

  6. Recent trends of projection X-ray microscopy in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yada, K. [Tohken CO., LTD. 2-27-7 Tamagawa Chofu, Tokyo 182-0025 (Japan)], E-mail: kyada@tohken.co.jp

    2009-08-15

    Recent activities of projection X-ray microscopy in Japan are reviewed. 1) By employing high brightness Schottky electron gun, resolution of 0.1 {mu}m is realized by Tohken CO. group and some application examples are shown. 2) Deblurring of Fresnel diffracted image formed by synchrotron orbital radiation (SOR) X-rays is successfully tried by Chiba University group. Remarkable Fresnel fringes appearing at HeLa cell are mostly reconstructed by an iteration method. 3) Element analysis is carried out by Meiji University group utilizing absorption-edge characteristics between two kinds of X-ray targets without X-ray spectrometer. Actually, Cu and Ni targets are used with an inter-changeable system for elemental analysis of Fe{sub 2}O{sub 3} particles and iron component in a mosquito larva.

  7. Scanning electron microscopy and X-ray spectroscopy applied to mycelial phase of sporothrix schenckii

    Directory of Open Access Journals (Sweden)

    M. Thibaut

    1975-04-01

    Full Text Available Scanning electron microscopy applied to the mycelial phase of Sporothrix schenckii shows a matted mycelium with conidia of a regular pattern. X-Ray microanalysis applied in energy dispersive spectroscopy and also in wavelength dispersive spectroscopy reveals the presence of several elements of Mendeleef's classification.Sporothrix schenckii foi estudado em microscopia eletrônica. Foram observados caracteres das hífas e dos esporos, vários elementos da classificação periódica foram postos em evidência graças à micro-análise a raios X.

  8. Electron probe X-ray microanalysis of boar and inobuta testes after the Fukushima accident

    Science.gov (United States)

    Yamashiro, Hideaki; Abe, Yasuyuki; Hayashi, Gohei; Urushihara, Yusuke; Kuwahara, Yoshikazu; Suzuki, Masatoshi; Kobayashi, Jin; Kino, Yasuyuki; Fukuda, Tomokazu; Tong, Bin; Takino, Sachio; Sugano, Yukou; Sugimura, Satoshi; Yamada, Takahisa; Isogai, Emiko; Fukumoto, Manabu

    2015-01-01

    We aimed to investigate the effect of chronic radiation exposure associated with the Fukushima Daiichi Nuclear Power Plant (FNPP) accident on the testes of boar and inobuta (a hybrid of Sus scrofa and Sus scrofa domestica). This study examined the contamination levels of radioactive caesium (Cs), especially 134Cs and 137Cs, in the testis of both boar and inobuta during 2012, after the Fukushima accident. Morphological analysis and electron-probe X-ray microanalysis (EPMA) were also undertaken on the testes. The 134Cs and 137Cs levels were 6430 ± 23 and 6820 ± 32 Bq/kg in the boar testes, and 755 ± 13 and 747 ± 17 Bq/kg in the inobuta testes, respectively. The internal and external exposure of total 134Cs and 137Cs in the boar testes were 47.1 mGy and 176.2 mGy, respectively, whereas in the inobuta testes, these levels were 6.09 mGy and 59.8 mGy, respectively. Defective spermatogenesis was not detected by the histochemical analysis of radiation-exposed testes for either animal. In neither animal were Cs molecules detected, using EPMA. In conclusion, we showed that adverse radiation-induced effects were not detected in the examined boar and inobuta testes following the chronic radiation exposure associated with the FNPP accident. PMID:26825300

  9. Gold nephropathy. Ultrastructural, fluorescent, and energy-dispersive x-ray microanalysis study

    Energy Technology Data Exchange (ETDEWEB)

    Ainsworth, S.K.; Swain, R.P.; Watabe, N.; Brackett, N.C. Jr.; Pilia, P.; Hennigar, G.R.

    1981-07-01

    The nephrotic syndrome developed in a patient receiving therapy with gold for rheumatoid arthritis. The results of a histopathological examination of the renal biopsy specimen were unremarkable. Immunofluorescent studies showed deposits of immunoglobulins and C3 in a granular pattern in the glomerular basement membranes. Ultrastructurally, the discrete osmiophilic immune complexes were epimembranous. By x-ray microanalysis, gold that was complexed with sulfur was present in proximal tubular cytoplasmic vacuoles and nuclei. Gold and sulfur could not be demonstrated in glomerular epimembranous deposits. The results of these studies suggest that immune complex deposition does not involve gold and sulfur acting as haptens. Gold-salt therapy may result in damage to proximal tubules that leak renal tubular antigens, which in turn complex with autoantibody and produce an autoimmune membranous nephropathy. The evidence for this mechanism is not convincing. Although the data indicate an immune-complex cause for gold-salt nephropathy, the incident antigen (or antigens) and mechanism of action remain unidentified.

  10. Strontium and bromide as tracers in X-ray microanalysis of biological tissue

    Energy Technology Data Exchange (ETDEWEB)

    Wroblewski, J.; Sagstroem, S.M.; Mulders, H.; Roomans, G.M. (Karolinska Institutet, Stockholm (Sweden))

    1989-09-01

    Since energy dispersive X-ray microanalysis cannot distinguish between isotopes of the same element, alternative methods have to be used to get information similar to that obtained in experiments with radioactive tracers. In the present study, strontium was used as a tracer for calcium, and bromide as a tracer for chloride. Rats were injected with strontium chloride in vivo, and the uptake of strontium in the acinar cells of the submandibular gland was studied. Eventually a Sr/Ca ratio of 0.3 was reached. In some animals, secretion of mucus had been elicited by stimulation with isoproterenol 4 h prior to injection of strontium chloride. Exchange of calcium for strontium was enhanced by prior injection with isoproterenol. In a second experiment, rats were injected with sodium bromide, and the uptake of bromide by the submandibular acinar cells was followed in time, both in pilocarpine-stimulated and unstimulated glands. Under the experimental conditions, bromide was rapidly taken up by the cells, and the cellular Br/Cl ratio was close to that found in serum. Submandibular glands take up Br somewhat faster than other tissues (liver, heart muscle, skeletal muscle). The uptake of Br in pancreatic acinar cells was studied in vitro. These experiments showed a 1:1 ratio (molar) exchange of Cl for Br.

  11. Scanning electron microscopy, x-ray diffraction, and electron microprobe analysis of calcific deposits on intrauterine contraceptive devices

    Energy Technology Data Exchange (ETDEWEB)

    Khan, S.R.; Wilkinson, E.J.

    1985-07-01

    Deposits found on intrauterine contraceptive devices (IUDs) were studied by scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray microanalysis. All seven devices, including five plastic and two copper IUDs, were coated with a crust containing cellular, acellular, and fibrillar material. The cellular material was composed of erythrocytes, leukocytes, cells of epithelial origin, sperm, and bacteria. Some of the bacteria were filamentous, with acute-angle branching. The fibrillar material appeared to be fibrin. Most of the acellular material was amorphous; calcite was identified by x-ray diffraction, and x-ray microanalysis showed only calcium. Some of the acellular material, particularly that on the IUD side of the crust, was organized in spherulitic crystals and was identified as calcium phosphate by x-ray microanalysis. The crust was joined to the IUD surface by a layer of fibrillar and amorphous material. It is suggested that the initial event in the formation of calcific deposits on IUD surfaces is the deposition of an amorphous and fibrillar layer. Various types of cells present in the endometrial environment adhere to this layer and then calcify. Thus, the deposition of calcific material on the IUDs is a calcification phenomenon, not unlike the formation of plaque on teeth.

  12. Three stages of copper accumulation in hepatocellular lysosomes: X-ray microanalysis of copper-loaded golden hamsters.

    OpenAIRE

    Yagi, A.; Hayashi, H; Higuchi, T.; Hishida, N.; Sakamoto, N.

    1992-01-01

    Male golden hamsters were loaded with copper by supplying them for up to 12 weeks with drinking water containing 0.5% cupric acetate. The copper feeding increased hepatic copper to widely varying levels. Energy dispersive X-ray microanalysis could always identify a copper-sulphur complex in the hepatocyte lysosomes of copper-loaded hamsters and the X-ray intensity of copper was found to be a reliable parameter to measure in-situ copper accumulation. Combining this parameter with the copper bi...

  13. Exploring nanomagnetism with soft x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, P.; Kim, D.-H.; Mesler, B.L.; Chao, W.; Sakdinawat,A.E.; Anderson, E.H.

    2006-10-30

    Magnetic soft X-ray microscopy images magnetism in nanoscale systems with a spatial resolution down to 15nm provided by state-of-the-art Fresnel zone plate optics. X-ray magnetic circular dichroism (X-MCD) is used as element-specific magnetic contrast mechanism similar to photoemission electron microscopy (PEEM), however, with volume sensitivity and the ability to record the images in varying applied magnetic fields which allows to study magnetization reversal processes at fundamental length scales. Utilizing a stroboscopic pump-probe scheme one can investigate fast spin dynamics with a time resolution down to 70 ps which gives access to precessional and relaxation phenomena as well as spin torque driven domain wall dynamics in nanoscale systems. Current developments in zone plate optics aim for a spatial resolution towards 10nm and at next generation X-ray sources a time resolution in the fsec regime can be envisioned.

  14. High spatial resolution soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Meyer-Ilse, W.; Medecki, H.; Brown, J.T. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    A new soft x-ray microscope (XM-1) with high spatial resolution has been constructed by the Center for X-ray Optics. It uses bending magnet radiation from beamline 6.1 at the Advanced Light Source, and is used in a variety of projects and applications in the life and physical sciences. Most of these projects are ongoing. The instrument uses zone plate lenses and achieves a resolution of 43 nm, measured over 10% to 90% intensity with a knife edge test sample. X-ray microscopy permits the imaging of relatively thick samples, up to 10 {mu}m thick, in water. XM-1 has an easy to use interface, that utilizes visible light microscopy to precisely position and focus the specimen. The authors describe applications of this device in the biological sciences, as well as in studying industrial applications including structured polymer samples.

  15. Idiopathic calcinosis of the scrotum: Scanning electron microscopic study with x-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Fuezesi, L.H.; Hollweg, G.; Lagrange, W.; Mittermayer, C. (Technical Univ., Aachen (West Germany))

    1991-03-01

    In a 31-year-old man 12 nodules up to 1 cm in diameter were observed in the scrotum; these had developed over 3 years. Energy-dispersive x-ray analysis of the dermal foci showed a high content of calcium and phosphorus even in nodules smaller than 1 mm in diameter. No increased mineral deposition was observed in the surrounding connective tissue, however. Scanning electron microscopy revealed finely granulated crystals, and cellular remnants giving rise to development of calcified nodules were disclosed. The results support the hypothesis of a degenerative origin of scrotal calcinosis.

  16. Applications of Hard X-ray Full-Field Transmission X-ray Microscopy at SSRL

    Science.gov (United States)

    Liu, Y.; Andrews, J. C.; Meirer, F.; Mehta, A.; Gil, S. Carrasco; Sciau, P.; Mester, Z.; Pianetta, P.

    2011-09-01

    State-of-the-art hard x-ray full-field transmission x-ray microscopy (TXM) at beamline 6-2C of Stanford Synchrotron Radiation Lightsource has been applied to various research fields including biological, environmental, and material studies. With the capability of imaging a 32-micron field-of-view at 30-nm resolution using both absorption mode and Zernike phase contrast, the 3D morphology of yeast cells grown in gold-rich media was investigated. Quantitative evaluation of the absorption coefficient was performed for mercury nanoparticles in alfalfa roots exposed to mercury. Combining XANES and TXM, we also performed XANES-imaging on an ancient pottery sample from the Roman pottery workshop at LaGraufesenque (Aveyron).

  17. X-ray microanalysis in cryosections of natively frozen Paramecium caudatum with regard to ion distribution in ciliates

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, M.; Meyer, R.; Zierold, K.

    1985-01-01

    Cells of Paramecium caudatum were shock-frozen without pretreatment for cryoultramicrotomy and freeze-dried for subsequent X-ray microanalysis. Na, Mg, P, S, Cl, K, and Ca were detected in different amounts in several subcellular compartments. In particular, calcium was localized below the cell surface (pellicle). Trichocysts were found to contain significant amounts of Na in their base but not in the tip. Na, Mg, P, S, Cl, K, Ca were found in electron dense deposits within the lumen of the contractile vacuole. A small K concentration was found in the cytoplasm and in the mitochondria. X-ray microanalysis of the element distribution in different subcellular compartments provides information for the understanding of cellular functions such as exocytosis, locomotion, and ion regulation.

  18. Genomics and X-ray microanalysis indicate that Ca2+ and thiols mediate the aggregation and adhesion of Xylella fastidiosa

    Directory of Open Access Journals (Sweden)

    Leite B.

    2002-01-01

    Full Text Available The availability of the genome sequence of the bacterial plant pathogen Xylella fastidiosa, the causal agent of citrus variegated chlorosis, is accelerating important investigations concerning its pathogenicity. Plant vessel occlusion is critical for symptom development. The objective of the present study was to search for information that would help to explain the adhesion of X. fastidiosa cells to the xylem. Scanning electron microscopy revealed that adhesion may occur without the fastidium gum, an exopolysaccharide produced by X. fastidiosa, and X-ray microanalysis demonstrated the presence of elemental sulfur both in cells grown in vitro and in cells found inside plant vessels, indicating that the sulfur signal is generated by the pathogen surface. Calcium and magnesium peaks were detected in association with sulfur in occluded vessels. We propose an explanation for the adhesion and aggregation process. Thiol groups, maintained by the enzyme peptide methionine sulfoxide reductase, could be active on the surface of the bacteria and appear to promote cell-cell aggregation by forming disulfide bonds with thiol groups on the surface of adjacent cells. The enzyme methionine sulfoxide reductase has been shown to be an auxiliary component in the adhesiveness of some human pathogens. The negative charge conferred by the ionized thiol group could of itself constitute a mechanism of adhesion by allowing the formation of divalent cation bridges between the negatively charged bacteria and predominantly negatively charged xylem walls.

  19. X-ray microanalysis of rotavirus-infected mouse intestine: A new concept of diarrhoeal secretion

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, A.J.; Osborne, M.P.; Haddon, S.J.; Collins, J.; Starkey, W.G.; Candy, D.C.; Stephen, J. (Univ. of Birmingham (England))

    1990-05-01

    Neonatal mice were infected at 7 days of age with rotavirus (epizootic diarrhea of infant mice (EDIM) virus) and killed at 24-h intervals postinfection (PI). Cytoplasmic concentrations of Na, Mg, P, S, Cl, K, and Ca intestinal epithelial cells from infected and age-matched control animals were measured by x-ray microanalysis. In villus tip cells, Ca concentration increased at 24-96 h PI; Na concentration increased at 24-72 h PI; Ca and Na concentrations were near normal by 168 h PI. K concentration decreased 24-72 h PI, and Cl concentration decreased 48-96 h PI. In crypt cells, changes were observed without a discernible pattern: at 96 h PI, Na, Mg, S, and Cl concentrations increased and K concentration decreased; at 120 h PI, the concentrations of all elements except Na and Ca increased. In villus base cells, the mean concentrations of all elements except Ca peaked at 48-72 h PI and at 120 h PI. Na and Cl concentrations increased dramatically in some cells from 48 h PI onward. All the above concentration values were obtained from freeze-dried specimens and expressed in millimoles per kilogram of dry weight. Conversion of a limited number of data, pertaining to villus base cells, from dry weight to wet weight was possible. This conversion revealed that villus base cells in infected animals were more hydrated than corresponding cells from control animals. Also, the Na and Cl concentrations in mmol/kg H2O were significantly higher in villus base cells from infected animals than in those from corresponding controls: 137 +/- 7 versus 38 +/- 4 (Na) and 121 +/- 5 versus 89 +/- 6 (Cl). Wet weight concentrations of other elements were either the same (Mg) or lower (P, S, and K) after infection with virus.

  20. Quantitative energy-dispersive electron probe X-ray microanalysis for single-particle analysis and its application for characterizing atmospheric aerosol particles

    Indian Academy of Sciences (India)

    Shila Maskey; Chul-Un Ro

    2011-02-01

    An energy-dispersive electron probe X-ray microanalysis (ED-EPMA) technique using an energy-dispersive X-ray detector with an ultra-thin window, designated as low-Z particle EPMA, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements such as C, N and O, as well as higher-Z elements that can be analysed by conventional ED-EPMA. The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulphates, nitrates, ammonium and carbonaceous particles, contain low-Z elements. To demonstrate its practical applicability, the application of the low-Z particle EPMA for the characterization of Asian Dust, urban and subway aerosol particles is shown herein. In addition, it is demonstrated that the Monte Carlo calculation can also be applied in a quantitative single-particle analysis using transmission electron microscopy (TEM) coupled with energy-dispersive X-ray spectrometry (EDX), showing that the technique is useful and reliable for the characterization of submicron aerosol particles

  1. X-ray fluorescence microscopy of olfactory receptor neurons

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-09-01

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

  2. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, A. P., E-mail: aph@mcmaster.ca; Lee, V.; Wu, J.; Cooper, G. [Chemistry & Chemical Biology, McMaster University, Hamilton, ON, L8S 4M1 (Canada); West, M. M.; Berejnov, V. [Faculty of Health Sciences Electron Microscopy, McMaster University, Hamilton, ON L8N 3Z5 (Canada); Soboleva, T.; Susac, D.; Stumper, J. [Automotive Fuel Cell Cooperation Corp., Burnaby BC V5J 5J8 (Canada)

    2016-01-28

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined.

  3. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    Science.gov (United States)

    Hitchcock, A. P.; Lee, V.; Wu, J.; West, M. M.; Cooper, G.; Berejnov, V.; Soboleva, T.; Susac, D.; Stumper, J.

    2016-01-01

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined.

  4. Blue light-dependent changes in loosely bound calcium in Arabidopsis mesophyll cells: an X-ray microanalysis study.

    Science.gov (United States)

    Łabuz, Justyna; Samardakiewicz, Sławomir; Hermanowicz, Paweł; Wyroba, Elżbieta; Pilarska, Maria; Gabryś, Halina

    2016-06-01

    Calcium is involved in the signal transduction pathway from phototropins, the blue light photoreceptor kinases which mediate chloroplast movements. The chloroplast accumulation response in low light is controlled by both phot1 and phot2, while only phot2 is involved in avoidance movement induced by strong light. Phototropins elevate cytosolic Ca(2+) after activation by blue light. In higher plants, both types of chloroplast responses depend on Ca(2+), and internal calcium stores seem to be crucial for these processes. Yet, the calcium signatures generated after the perception of blue light by phototropins are not well understood. To characterize the localization of calcium in Arabidopsis mesophyll cells, loosely bound (exchangeable) Ca(2+) was precipitated with potassium pyroantimonate and analyzed by transmission electron microscopy followed by energy-dispersive X-ray microanalysis. In dark-adapted wild-type Arabidopsis leaves, calcium precipitates were observed at the cell wall, where they formed spherical structures. After strong blue light irradiation, calcium at the apoplast prevailed, and bigger, multilayer precipitates were found. Spherical calcium precipitates were also detected at the tonoplast. After red light treatment as a control, the precipitates at the cell wall were smaller and less numerous. In the phot2 and phot1phot2 mutants, calcium patterns were different from those of wild-type plants. In both mutants, no elevation of calcium after blue light treatment was observed at the cell periphery (including the cell wall and a fragment of cytoplasm). This result confirms the involvement of phototropin2 in the regulation of Ca(2+) homeostasis in mesophyll cells.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-08-11

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

  6. Imaging bacterial spores by soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stead, A.D.; Ford, T.W. [Univ. of London, Surrey (United Kingdom); Judge, J. [Unilever plc, Sharnbrook (United Kingdom)] [and others

    1997-04-01

    Bacterial spores are able to survive dehydration, but neither the physiological nor structural basis of this have been fully elucidated. Furthermore, once hydrated, spores often require activation before they will germinate. Several treatments can be used to activate spores, but in the case of Bacillus subtlis the most effective is heat treatment. The physiological mechanism associated with activation is also not understood, but some workers suggest that the loss of calcium from the spores may be critical. However, just prior to germination, the spores change from being phase bright to phase dark when viewed by light microscopy. Imaging spores by soft x-ray microscopy is possible without fixation. Thus, in contrast to electron microscopy, it is possible to compare the structure of dehydrated and hydrated spores in a manner not possible previously. A further advantage is that it is possible to monitor individual spores by phase contrast light microscopy immediately prior to imaging with soft x-rays; whereas, with both electron microscopy and biochemical studies, it is a population of spores being studied without knowledge of the phase characteristics of individual spores. This study has therefore tried to compare dehydrated and hydrated spores and to determine if there is a mass loss from individual spores as they pass the transition from being phase bright to phase dark.

  7. [Results of an investigation of enamel fragments from Benvenuto Cellini's "Saliera" using energy-dispersive X-ray microanalysis (EDX)].

    Science.gov (United States)

    Ditrich, Hans

    2009-01-01

    A blackmail letter was submitted in the context of the theft of Cellini's salt cellar (Saliera) from the Museum of Fine Arts in Vienna. Dark blue enamel fragments were included in this letter as a proof of authenticity. The comparison of this material with enamel believed to originate from the original artwork, using microspectrography and energy-dispersive X-ray microanalysis (EDX) in the scanning electron microscope showed similar elemental composition. Accordingly, the further investigations could concentrate on this blackmail attempt in spite of numerous other confession letters received.

  8. Beryllium detection in human lung tissue using electron probe X-ray microanalysis.

    Science.gov (United States)

    Butnor, Kelly J; Sporn, Thomas A; Ingram, Peter; Gunasegaram, Sue; Pinto, John F; Roggli, Victor L

    2003-11-01

    Chronic berylliosis is an uncommon disease that is caused by the inhalation of beryllium particles, dust, or fumes. The distinction between chronic berylliosis and sarcoidosis can be difficult both clinically and histologically, as both entities can have similar presentations and exhibit nonnecrotizing granulomatous inflammation of the lungs. The diagnosis of chronic berylliosis relies on a history of exposure to beryllium, roentgenographic evidence of diffuse nodular disease, and demonstration of beryllium hypersensitivity by ancillary studies, such as lymphocyte proliferation testing. Additional support may be gained by the demonstration of beryllium in lung tissue. Unlike other exogenous particulates, such as asbestos, detection of beryllium in human lung tissue is problematic. The low atomic number of beryllium usually makes it unsuitable for conventional microprobe analysis. We describe a case of chronic berylliosis in which beryllium was detected in lung tissue using atmospheric thin-window energy-dispersive X-ray analysis (ATW EDXA). A woman with a history of occupational exposure to beryllium at a nuclear weapons testing facility presented with progressive cough and dyspnea and a nodular pattern on chest roentgenograph. Open lung biopsy showed nonnecrotizing granulomatous inflammation that was histologically indistinguishable from sarcoidosis. Scanning electron microscopy and ATW EDXA demonstrated particulates containing beryllium within the granulomas. This application of EDXA offers significant advantages over existing methods of beryllium detection in that it is nondestructive, more widely available, and can be performed using routine paraffin sections.

  9. X-ray absorption measurement by scanning capacitance microscopy

    Science.gov (United States)

    Ishii, Masashi; Uchihashi, Takayuki

    2003-12-01

    This paper describes a demonstration of scanning capacitance microscopy (SCM) as a technique for measuring X-ray absorption fine structure (XAFS) in what is called the SCM-XAFS method. This method achieves the simultaneous analysis of the electrical and chemical characteristics of surface-trapping centers. In obtaining the XAFS spectrum of trapping centers, the method takes advantage of the fact that the X-ray-induced photoemission of a localized electron leads to a change in capacitance. When the Fermi level corresponds to the trapping level, the photoemission process is sensitively detected. Therefore, a specific trapping center may be selectively observed by controlling the bias. From SCM-XAFS measurements of a GaAs surface, we found that gallium oxide trapping centers capture electrons in the positive bias voltage region. Moreover, experimental findings that resonant intra-transition and resonant scattering of emitted photoelectrons enhance the SCM-XAFS signal at particular X-ray photon energy reveal the local density of states of the gallium oxide and the complex structure of the trapping centers.

  10. Scanning X-ray microscopy of superconductor/ferromagnet bilayers

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Claudia; Ruoss, Stephen; Weigand, Markus; Schuetz, Gisela [Max Planck Institute for Intelligent Systems, Stuttgart (Germany); Zahn, Patrick; Bayer, Jonas [Max Planck Institute for Intelligent Systems, Stuttgart (Germany); Research Institute for Innovative Surfaces, FINO, Aalen University (Germany); Albrecht, Joachim [Research Institute for Innovative Surfaces, FINO, Aalen University (Germany)

    2016-07-01

    The magnetic flux distribution arising from a high-T{sub c} superconductor is detected and visualized with high spatial resolution using scanning x-ray microscopy (SXM). Therefore, we introduce a sensor layer, namely, an amorphous, soft-magnetic CoFeB cover layer. The magnetic stray fields of the supercurrents lead to a local reorientation of the magnetic moments in the ferromagnet, which is visualized using the large x-ray magnetic circular dichroism (XMCD) effect of the Co and Fe L3-edge. We show that the XMCD contrast in the sensor layer corresponds to the in-plane magnetic flux distribution of the superconductor and can hence be used to image magnetic structures in superconductors with high spatial resolution. Using the total electron yield (TEY) mode the surface structure and the magnetic domains can be imaged simultaneously and can be correlated. The measurements are carried out at our scanning x-ray microscope MAXYMUS at Bessy II, Berlin with the new low temperature setup.

  11. Chemometric classification of gunshot residues based on energy dispersive X-ray microanalysis and inductively coupled plasma analysis with mass-spectrometric detection

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, S. [Bundeskriminalamt (BKA), Forensic Science Institute KT23, Thaerstr. 11, D - 65193 Wiesbaden (Germany); Otto, M. [TU Bergakademie Freiberg (TU BAF), Institute for Analytical Chemistry, Leipziger Str. 29, D - 09599 Freiberg (Germany)], E-mail: matthias.otto@chemie.tu-freiberg.de; Niewoehner, L.; Barth, M. [Bundeskriminalamt (BKA), Forensic Science Institute KT23, Thaerstr. 11, D - 65193 Wiesbaden (Germany); Brozek-Mucha, Z. [Instytut Ekspertyz Sadowych (IES), Westerplatte St. 9, PL - 31-033 Krakow (Poland); Biegstraaten, J. [Nederlands Forensisch Instituut (NFI), Fysische Technologie, Laan van Ypenburg 6, NL-2497 GB Den Haag (Netherlands); Horvath, R. [Kriminalisticky a Expertizny Ustav (KEU PZ), Institute of Forensic Science, Sklabinska 1, SK - 812 72 Bratislava (Slovakia)

    2007-09-15

    A gunshot residue sample that was collected from an object or a suspected person is automatically searched for gunshot residue relevant particles. Particle data (such as size, morphology, position on the sample for manual relocation, etc.) as well as the corresponding X-ray spectra and images are stored. According to these data, particles are classified by the analysis-software into different groups: 'gunshot residue characteristic', 'consistent with gunshot residue' and environmental particles, respectively. Potential gunshot residue particles are manually checked and - if necessary - confirmed by the operating forensic scientist. As there are continuing developments on the ammunition market worldwide, it becomes more and more difficult to assign a detected particle to a particular ammunition brand. As well, the differentiation towards environmental particles similar to gunshot residue is getting more complex. To keep external conditions unchanged, gunshot residue particles were collected using a specially designed shooting device for the test shots revealing defined shooting distances between the weapon's muzzle and the target. The data obtained as X-ray spectra of a number of particles (3000 per ammunition brand) were reduced by Fast Fourier Transformation and subjected to a chemometric evaluation by means of regularized discriminant analysis. In addition to the scanning electron microscopy in combination with energy dispersive X-ray microanalysis results, isotope ratio measurements based on inductively coupled plasma analysis with mass-spectrometric detection were carried out to provide a supplementary feature for an even lower risk of misclassification.

  12. X-ray microscopy of soft and hard human tissues

    Energy Technology Data Exchange (ETDEWEB)

    Müller, Bert, E-mail: bert.mueller@unibas.ch; Schulz, Georg, E-mail: georg.schulz@unibas.ch; Deyhle, Hans, E-mail: hans.deyhle@unibas.ch; Stalder, Anja K., E-mail: anja.stalder@unibas.ch; Ilgenstein, Bernd, E-mail: bernd.ilgenstein@unibas.ch; Holme, Margaret N., E-mail: m.holme@imperial.ac.uk; Hieber, Simone E., E-mail: simone.hieber@unibas.ch [Biomaterials Science Center (BMC), University of Basel, c/o University Hospital, 4031 Basel (Switzerland); Weitkamp, Timm, E-mail: weitkamp@synchrotron-soleil.fr [Beamline ANATOMIX, Synchrotron Soleil, L’Orme des Merisiers, Saint Aubin - B.P. 48, 91192 Gif sur Yvette (France); Beckmann, Felix, E-mail: felix.beckmann@hzg.de [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht, c/o HZG at DESY, Notkestr. 85, 22607 Hamburg (Germany)

    2016-01-28

    The simultaneous post mortem visualization of soft and hard tissues using absorption-based CT remains a challenge. If the photon energy is optimized for the visualization of hard tissue, the surrounding soft tissue components are almost X-ray transparent. Therefore, the combination with other modalities such as phase-contrast CT, magnetic resonance microscopy, and histology is essential to detect the anatomical features. The combination of the 2D and 3D data sets using sophisticated segmentation and registration tools allows for conclusions about otherwise inaccessible anatomical features essential for improved patient treatments.

  13. Comparative studies of elemental composition on ejaculated fowl, bull, rat, dog and boar spermatozoa by electron probe X-ray microanalysis.

    Science.gov (United States)

    Ashizawa, K; Ozawa, Y; Okauchi, K

    1987-01-01

    1. Comparative analyses of the concentrations of bulk and trace elements on the head, midpiece and tail regions of the ejaculated fowl, bull, rat, dog and boar spermatozoa were performed using X-ray microanalysis with scanning electron microscopy. 2. Although the pattern of distribution of elements on the surface of the three different subcellular regions was, in general, similar among all the species, there were substantial shifts in absolute concentrations. 3. Concentration of magnesium on the dog spermatozoa was significantly higher (about 2 times) than those of the other species. 4. Zinc, copper, iron and manganese concentrations were higher on fowl spermatozoa compared with those of the other species studied. 5. The Na-to-K ratios on the midpiece ranged from 1.46 (rat) to 2.26 (dog).

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-12-15

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

  15. Scanning and transmission electron microscopy of a craniopharyngioma: x-ray microanalytical study of the intratumoral mineralized deposits

    Energy Technology Data Exchange (ETDEWEB)

    Vilches, J.; Lopez, A.; Martinez, M.C.; Gomez, J.; Barbera, J.

    This paper discusses the value of scanning electron microscopy (SEM) and x-ray microanalysis in the classification of craniopharyngiomas. This neoplasm shows epithelial nest, cords of cuboid cells, foci of squamous metaplasia, and microcystic degeneration. SEM reveals that the epithelial cysts are lined with elongated cells that possess numerous microvilli and blebs and that some cysts are lined with polyhedral cells. The microvilli are interpreted as characteristic of the fast growing craniopharyngiomas. A microanalytical study of the calcified areas reveals the presence of magnesium, phosphorus, and calcium.

  16. Full-field hard x-ray microscopy with interdigitated silicon lenses

    DEFF Research Database (Denmark)

    Simons, Hugh; Stöhr, Frederik; Michael-Lindhard, Jonas

    2016-01-01

    Full-field x-ray microscopy using x-ray objectives has become a mainstay of the biological and materials sciences. However, the inefficiency of existing objectives at x-ray energies above 15 keV has limited the technique to weakly absorbing or two-dimensional (2D) samples. Here, we show...

  17. Use of the cerium chloride technique and energy dispersive X-ray microanalysis in plant peroxisome identification

    Energy Technology Data Exchange (ETDEWEB)

    Kausch, A.P.; Wagner, B.L.; Horner, H.T. (Iowa State Univ. of Science and Technology, Ames (USA))

    1983-01-01

    Glycolate oxidase activity is demonstrated cytochemically with the CeCl/sub 3/ technique in leaf peroxisomes of Nicotiana tabacum, Glycine max, Psychotria punctata and in unspecialized peroxisomes of Yucca torreyi roots. Reaction product deposition occurs throughout peroxisomal matrices, whereas nucleoid inclusion bodies, occurring in all four species, are cytochemically unreactive. We observed reactive and nonreactive microbodies within individual cells in these four plants despite prolonged incubation times and increased CeCl/sub 3/ concentration. These results may reflect differences in glycolate oxidase content or peroxisomal differentiation within individual cells of a given tissue. We demonstrate substrate-independent cerium deposits in cell walls, cytoplasmic hoop-shaped structures and chloroplast thylakoids at extended incubation times or increased CeCl/sub 3/ concentration, perhaps indicating the presence of endogenous H/sub 2/O/sub 2/. Elemental spectral analysis of electron-dense deposits with energy dispersive X-ray microanalysis using a STEM detects peaks generated from the L-series of cerium. SEM X-ray mapping for the Lsub(..cap alpha..1) peak of cerium verifies peroxisomal localization of reaction product in thin sections.

  18. PREFACE: 9th International Conference on X-Ray Microscopy

    Science.gov (United States)

    Quitmann, Christoph; David, Christian; Nolting, Frithjof; Pfeiffer, Franz; Stampanoni, Marco

    2009-09-01

    Conference logo This volume compiles the contributions to the International Conference on X-Ray Microscopy (XRM2008) held on 20-25 July 2008 in Zurich, Switzerland. The conference was the ninth in a series which started in Göttingen in 1984. Over the years the XRM conference series has served as a forum bringing together all relevant players working on the development of methods, building instrumentation, and applying x-ray microscopy to challenging issues in materials science, condensed matter research, environmental science and biology. XRM2008 was attended by about 300 participants who followed 44 oral presentations and presented 220 posters. Conference photograph Figure 1: Participants of the XRM2008 conference gathered in front of the main building of the ETH-Zurich. The conference showed that x-ray microscopy has become a mature field resting on three pillars. The first are workhorse instruments available even to non-specialist users. These exist at synchrotron sources world-wide as well as in laboratories. They allow the application of established microscopy methods to solve scientific projects in areas as diverse as soil science, the investigation of cometary dust particles, magnetic materials, and the analysis of ancient parchments. Examples of all of these projects can be found in this volume. These instruments have become so well understood that now they are also commercially available. The second pillar is the continued development of methods. Methods like stroboscopic imaging, wet cells or high and low temperature environments add versatility to the experiments. Methods like phase retrieval and ptychographic imaging allow the retrieval of information which hitero was thought to be inaccessible. The third pillar is the extension of such instruments and methods to new photon sources. With x-ray free electron lasers on the horizon the XRM community is working to transfer their know-how to these novel sources which will offer unprecedented brightness and

  19. The detection of sulphur in contamination spots in electron probe X-ray microanalysis

    Science.gov (United States)

    Adler, I.; Dwornik, E.J.; Rose, H.J.

    1962-01-01

    Sulphur has been identified as one of the elements present in the contamination spot which forms under the electron beam in the microprobe. The presence of the sulphur results in a rapid change in intensity measurements causing a loss of observed intensity for elements other than sulphur. The source of sulphur has been traced at least in part to the Apiezon B diffusion pump oil. A comparative X-ray fluorescence study of the Apiezon B and Octoil diffusion pump oils showed substantial amounts of sulphur in the Apiezon B. The Octoil was relatively free of sulphur.

  20. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy?

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, K.; Adams, F. [Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry; Rivers, M.L.; Jones, K.W. [Brookhaven National Lab., Upton, NY (United States)

    1992-10-01

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ({mu}-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  1. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, K.; Adams, F. (Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry); Rivers, M.L.; Jones, K.W. (Brookhaven National Lab., Upton, NY (United States))

    1992-01-01

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ([mu]-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  2. Microbial biofilm study by synchrotron X-ray microscopy

    Science.gov (United States)

    Pennafirme, S.; Lima, I.; Bitencourt, J. A.; Crapez, M. A. C.; Lopes, R. T.

    2015-11-01

    Microbial biofilm has already being used to remove metals and other pollutants from wastewater. In this sense, our proposal was to isolate and cultivate bacteria consortia from mangrove's sediment resistant to Zn (II) and Cu (II) at 50 mg L-1 and to observe, through synchrotron X-ray fluorescence microscopy (microXRF), whether the biofilm sequestered the metal. The biofilm area analyzed was 1 mm2 and a 2D map was generated (pixel size 20×20 μm2, counting time 5 s/point). The biofilm formation and retention followed the sequence Zn>Cu. Bacterial consortium zinc resistant formed dense biofilm and retained 63.83% of zinc, while the bacterial consortium copper resistant retained 3.21% of copper, with lower biofilm formation. Dehydrogenase activity of Zn resistant bacterial consortium was not negatively affect by 50 mg ml-1 zinc input, whereas copper resistant bacterial consortium showed a significant decrease on dehydrogenase activity (50 mg mL-1 of Cu input). In conclusion, biofilm may protect bacterial cells, acting as barrier against metal toxicity. The bacterial consortia Zn resistant, composed by Nitratireductor spp. and Pseudomonas spp formed dense biofilm and sequestered metal from water, decreasing the metal bioavailability. These bacterial consortia can be used in bioreactors and in bioremediation programs.

  3. Unraveling the redox behavior of a CoMoS hydrodesulfurization catalyst : A scanning transmission X-ray microscopy study in the tender X-ray range

    NARCIS (Netherlands)

    Al Samarai, Mustafa; Meirer, Florian; Karunakaran, Chithra; Wang, Jian; Vogt, Eelco T C; Zandbergen, Henny W.; Weber, Thomas; Weckhuysen, Bert M.; De Groot, Frank M F

    2015-01-01

    We visualize the elemental zoning in an alumina-supported cobalt molybdenum sulfide (CoMoS) catalyst with scanning transmission X-ray microscopy (STXM). We use the Canadian Light Source beamline 10-ID's (SM) unique combination of soft X-ray and tender X-ray STXM to determine the spatial variation of

  4. X-ray induced chemical reaction revealed by in-situ X-ray diffraction and scanning X-ray microscopy in 15 nm resolution (Conference Presentation)

    Science.gov (United States)

    Ge, Mingyuan; Liu, Wenjun; Bock, David; De Andrade, Vincent; Yan, Hanfei; Huang, Xiaojing; Marschilok, Amy; Takeuchi, Esther; Xin, Huolin; Chu, Yong S.

    2016-09-01

    The detection sensitivity of synchrotron-based X-ray techniques has been largely improved due to the ever increasing source brightness, which have significantly advanced ex-situ and in-situ research for energy materials, such as lithium-ion batteries. However, the strong beam-matter interaction arisen from the high beam flux can significantly modify the material structure. The parasitic beam-induced effect inevitably interferes with the intrinsic material property, which brings difficulties in interpreting experimental results, and therefore requires comprehensive evaluation. Here we present a quantitative in-situ study of the beam-effect on one electrode material Ag2VO2PO4 using four different X-ray probes with different radiation dose rate. The material system we reported exhibits interesting and reversible radiation-induced thermal and chemical reactions, which was further evaluated under electron microscopy to illustrate the underlying mechanism. The work we presented here will provide a guideline in using synchrotron X-rays to distinguish the materials' intrinsic behavior from extrinsic structure changed induced by X-rays, especially in the case of in-situ and operando study where the materials are under external field of either temperature or electric field.

  5. Soft X-ray scanning transmission X-ray microscopy (STXM) of actinide particles.

    Science.gov (United States)

    Nilsson, Hans J; Tyliszczak, Tolek; Wilson, Richard E; Werme, Lars; Shuh, David K

    2005-09-01

    A descriptive account is given of our most recent research on the actinide dioxides with the Advanced Light Source Molecular Environmental Science (ALS-MES) Beamline 11.0.2 soft X-ray scanning transmission X-ray microscope (STXM) at the Lawrence Berkeley National Laboratory (LBNL). The ALS-MES STXM permits near-edge X-ray absorption fine structure (NEXAFS) and imaging with 30-nm spatial resolution. The first STXM spectromicroscopy NEXAFS spectra at the actinide 4d5/2 edges of the imaged transuranic particles, NpO2 and PuO2, have been obtained. Radiation damage induced by the STXM was observed in the investigation of a mixed oxidation state particle (Np(V,VI)) and was minimized during collection of the actual spectra at the 4d5/2 edge of the Np(V,VI) solid. A plutonium elemental map was obtained from an irregular PuO2 particle with the dimensions of 650 x 650 nm. The Pu 4d5/2 NEXAFS spectra were collected at several different locations from the PuO2 particle and were identical. A representative oxygen K-edge spectrum from UO2 was collected and resembles the oxygen K-edge from the bulk material. The unique and current performance of the ALS-MES STXM at extremely low energies (ca. 100 eV) that may permit the successful measurement of the actinide 5d edge is documented. Finally, the potential of STXM as a tool for actinide investigations is briefly discussed.

  6. Ultrastructural localization of uranium biosorption in Penicillium digitatum by stem x-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Galun, M.; Siegel, S.M.; Cannon, M.I.; Siegel, B.Z.; Galun, E.

    1987-01-01

    When Penicillium digitatum Saccardo cultures are exposed to aqueous solutions containing soluble uranium salts, considerable amounts of this element are accumulated in the fungal mycelium. The accumulated uranium is retained after thorough rinsing with distilled water but is removed by alkali carbonate solutions. Analysis of thick sections (0.5 ..mu..m) of the fungal hyphae with TEM, after incubation in UO/sub 2/Cl/sub 2/ solutions of varying concentrations under both light and dark conditions, revealed conspicuous crystal-like deposits in UO/sub 2/Cl/sub 2/-exposed hyphae, but none in the control hyphae. Thick sections were necessary for crystal visualization. Using energy-dispersive X-ray analysis, uranium was detected as the only heavy element in these crystals. Uranium crystal biosorption was localized on the outside surface of the hyphal cell wall (following short exposures to relatively low uranium concentrations) or inside the cell wall (following long exposure to relatively high uranium concentrations). In some cases, crystal-like deposits of uranium salts were located on the outside surface as well as inside the cell.

  7. Integration of X-ray microanalysis and morphometry of biological material

    Energy Technology Data Exchange (ETDEWEB)

    de Bruijn, W.C.

    1985-01-01

    The authors investigated how to extract both morphometrical and X-ray elemental information from scanning electron microscopical (SEM) or scanning transmission electron microscopical (STEM)-images and how to integrate these two information streams either on line or off-line after storage. Cytochemical reaction products in cell organelles in ultrathin sections are the biological structures of interest. A new program has been proposed and described, which permits determination of both the area and the mean net-intensity value of chemical elements, inhomogeneously distributed over heteromorph organelles. The value of this integration method is demonstrated by three examples of increasing complexity, starting with two elements which are more or less homogeneously distributed over one lysosome, the establishing of a platinum discontinuity in an acidophilic granule and finally the localization of two chemical elements inhomogeneously distributed over a rather heteromorph phagolysosome. In two examples Chelex ion exchange beads, maximally loaded with the element also present in the structure of interest, are co-embedded with the tissue as internal standards. In such cases the absolute elemental concentration in the structures analysed can be established.

  8. Use of x-ray microanalysis to monitor diffusion of Zn from a cement into human dentin

    Energy Technology Data Exchange (ETDEWEB)

    Ashrafi, S.H.; Waterhouse, J.P.; Patel, M. (Departments of Oral Pathology, Oral Histology, Pathology and Research Resources Center, University of Illinois at Chicago, USA); Baratieri, A.; Picarelli, A.; Somma, F. (Istituto di Clinica Odontoiatrica, Universita Cattolica del Sacro Cuore, Rome, Italy)

    1983-01-01

    Energy dispersive x-ray spectrometry (EDAX system), with scanning electron microscopy was used to detect diffusion of Zn from a source in human dentin and the system was tested for sensitivity and reproducibility. Sections of human teeth in which a ZnO-eugenol cement had been placed in a cavity in the dentin in vivo were prepared and x-ray microanalytical measurements carried out. We found that values of counts for Zn, Ca and P in the same field were linear up to a total counting time of 60 sec. We further found that reproducibility of values between repeat examinations of the same specimens of different days was excellent. The concentration of Zn in the dentin decreased exponentially with distance from source within the distance tested. We conclude that the system can be used to detect trace concentrations of Zn, and that accordingly the diffusion behaviour of a variety of ions in dentin could be monitored.

  9. In-situ Scanning Transmission X-Ray Microscopy of Catalytic Solids and Related Nanomaterials

    NARCIS (Netherlands)

    de Groot, F.M.F.; de Smit, E.; van Schooneveld, M.M.; Aramburo, L.R.; Weckhuysen, B.M.

    2013-01-01

    The present status of in-situ scanning transmission X-ray microscopy (STXM) is reviewed, with an emphasis on the abilities of the STXM technique in comparison with electron microscopy. The experimental aspects and interpretation of X-ray absorption spectroscopy (XAS) are briefly introduced and the e

  10. Final Report on Small Particle Speciation for Forensics Analysis by Soft X-ray Scanning Transmission X-ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pacold, J. I. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Altman, A. B. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Donald, S B [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dai, Z. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Davisson, M. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Holliday, K S [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Knight, K. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kristo, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Minasian, S. G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nelson, A J [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tyliszczak, T [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Booth, C. H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shuh, D. K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-09-30

    Materials of interest for nuclear forensic science are often highly heterogeneous, containing complex mixtures of actinide compounds in a wide variety of matrices. Scanning transmission X-ray microscopy (STXM) is ideally suited to study such materials, as it can be used to chemically image specimens by acquiring X-ray absorption near-edge spectroscopy (XANES) data with 25 nm spatial resolution. In particular, STXM in the soft X-ray synchrotron radiation regime (approximately 120 – 2000 eV) can collect spectroscopic information from the actinides and light elements in a single experiment. Thus, STXM combines the chemical sensitivity of X-ray absorption spectroscopy with high spatial resolution in a single non-destructive characterization method. This report describes the application of STXM to a broad range of nuclear materials. Where possible, the spectroscopic images obtained by STXM are compared with information derived from other analytical methods, and used to make inferences about the process history of each material. STXM measurements can yield information including the morphology of a sample, “elemental maps” showing the spatial distribution of major chemical constituents, and XANES spectra from localized regions of a sample, which may show spatial variations in chemical composition.

  11. Viewing spin structures with soft X-ray microscopy

    Directory of Open Access Journals (Sweden)

    Peter Fischer

    2010-09-01

    Full Text Available The spin of the electron and it's associated magnetic moment marks the basic unit for magnetic properties of matter1,2. Magnetism, in particular ferromagnetism and antiferromagnetism is described by a collective order of these spins, where the interaction between individual spins reflects a competition between exchange, anisotropy and dipolar energy terms. As a result the energetically favored ground state of a ferromagnetic system is a rather complex spin configuration, the magnetic domain structure3. Magnetism is one of the eldest scientific phenomena, yet it is one of the most powerful and versatile utilized physical effects in modern technologies, such as in magnetic storage and sensor devices. To achieve highest storage density, the relevant length scales, such as the bit size in disk drives is now approaching the nanoscale and as such further developments have to deal with nanoscience phenomena4–9. Advanced characterization tools are required to fully understand the underlying physical principles. Magnetic microscopes using polarized soft X-rays offer a close-up view into magnetism with unique features, these include elemental sensitivity due to X-ray magnetic dichroism effects as contrast mechanism, high spatial resolution provided by state-of-the-art X-ray optics and fast time resolution limited by the inherent time structure of current X-ray sources, which will be overcome with the introduction of ultrafast and high brilliant X-ray sources.

  12. Viewing spin structures with soft x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Peter

    2010-06-01

    The spin of the electron and its associated magnetic moment marks the basic unit for magnetic properties of matter. Magnetism, in particular ferromagnetism and antiferromagnetism is described by a collective order of these spins, where the interaction between individual spins reflects a competition between exchange, anisotropy and dipolar energy terms. As a result the energetically favored ground state of a ferromagnetic system is a rather complex spin configuration, the magnetic domain structure. Magnetism is one of the eldest scientific phenomena, yet it is one of the most powerful and versatile utilized physical effects in modern technologies, such as in magnetic storage and sensor devices. To achieve highest storage density, the relevant length scales, such as the bit size in disk drives is now approaching the nanoscale and as such further developments have to deal with nanoscience phenomena. Advanced characterization tools are required to fully understand the underlying physical principles. Magnetic microscopes using polarized soft X-rays offer a close-up view into magnetism with unique features, these include elemental sensitivity due to X-ray magnetic dichroism effects as contrast mechanism, high spatial resolution provided by state-of-the-art X-ray optics and fast time resolution limited by the inherent time structure of current X-ray sources, which will be overcome with the introduction of ultrafast and high brilliant X-ray sources.

  13. A chemical signal possibly related to physiology in fossil cells detected by energy dispersive X-ray microanalysis.

    Science.gov (United States)

    Wang, X

    2006-02-01

    Energy dispersive X-ray microanalysis (EDXMA) is a widely used tool employed to detect elemental composition and its spatial distribution in a sample without causing damage. Charcoalified cytoplasm is a new type of fossil material that came to people's attention only recently. In this paper, EDXMA is used for the first time to detect the spatial elemental distribution in charcoalified cytoplasm of two fossil plants that are more than 100 million years old. The results demonstrate certain elemental distribution patterns within charcoalified cytoplasm and the surrounding cell walls. Based on the results from cytological studies of extant material, the heterogeneous spatial elemental distribution within the charcoalified cytoplasm has the potential to be related to the maturation of cells, the presence of certain organelles, and the physiology of these organelles. This is the first chemical signal detected in cytoplasm residue that can possibly be related to plant physiology. This paves the way for further research on fossil cytoplasm, which will better our understanding on the physiology of fossil plants.

  14. Processes modulating calcium distribution in citrus leaves. An investigation using x-ray microanalysis with strontium as a tracer.

    Science.gov (United States)

    Storey, Richard; Leigh, Roger A

    2004-11-01

    Citrus leaves accumulate large amounts of calcium that must be compartmented effectively to prevent stomatal closure by extracellular Ca2+ and interference with Ca(2+)-based cell signaling pathways. Using x-ray microanalysis, the distribution of calcium between vacuoles in different cell types of leaves of rough lemon (Citrus jambhiri Lush.) was investigated. Calcium was accumulated principally in palisade, spongy mesophyll, and crystal-containing idioblast cells. It was low in epidermal and bundle sheath cells. Potassium showed the reverse distribution. Rubidium and strontium were used as tracers to examine the pathways by which potassium and calcium reached these cells. Comparisons of strontium and calcium distribution indicated that strontium is a good tracer for calcium, but rubidium did not mirror the potassium distribution pattern. The amount of strontium accumulated was highest in palisade cells, lowest in bundle sheath and epidermal cells, and intermediate in the spongy mesophyll. Accumulation of strontium in palisade and spongy mesophyll was accompanied by loss of potassium from these cells and its accumulation in the bundle sheath. Strontium moved apoplastically from the xylem to all cell types, and manipulation of water loss from the adaxial leaf surface suggested that diffusion is responsible for strontium movement to this side of the leaf. The results highlight the importance of palisade and spongy mesophyll as repositories for calcium and suggest that calcium distribution between different cell types is the result of differential rates of uptake. This tracer technique can provide important information about the ion uptake and accumulation properties of cells in intact leaves.

  15. Evaluation of the viability of cultured corneal endothelial cells by quantitative electron probe X-ray microanalysis.

    Science.gov (United States)

    Alaminos, M; Sanchez-Quevedo, M C; Muñoz-Avila, J I; García, J M; Crespo, P V; González-Andrades, M; Campos, A

    2007-06-01

    Construction of artificial organs and tissues by tissue engineering is strongly dependent on the availability of viable cells. For that reason, the viability and the physiological status of cells kept in culture must be evaluated before the cells can be used for clinical purposes. In this work, we determined the viability of isolated rabbit corneal endothelial cells by trypan blue staining and quantitative electron probe X-ray microanalysis. Our results showed that the ionic content of potassium in cultured corneal endothelial cells tended to rise initially, but significantly decreased in cells in the fifth (and final) subculture, especially in comparison to cells in the fourth subculture (P subculture than in the fourth subculture (P subculture (P = 0.031). These data imply a remarkable decrease in the K/Na ratio from the fourth to the fifth subculture. Our microanalytical results, along with the morphological differences between cells in the last two subcultures, are compatible with an early phase of the preapoptotic process in the fifth subculture, and suggest that cells of the first four subcultures would be better candidates for tissue engineering.

  16. Magnetic soft x-ray microscopy-imaging fast spin dynamics inmagnetic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Peter; Kim, Dong-Hyun; Mesler, Brooke L.; Chao, Weilun; Sakdinawat, Anne E.; Anderson, Erik H.

    2007-06-01

    Magnetic soft X-ray microscopy combines 15nm spatial resolution with 70ps time resolution and elemental sensitivity. Fresnel zone plates are used as X-ray optics and X-ray magnetic circular dichroism serves as magnetic contrast mechanism. Thus scientifically interesting and technologically relevant low dimensional nanomagnetic systems can be imaged at fundamental length and ultrafast time scales in a unique way. Studies include magnetization reversal in magnetic multilayers, nanopatterned systems, vortex dynamics in nanoelements and spin current induced phenomena.

  17. [The x-ray microanalysis of the mucosa of the rat small intestine].

    Science.gov (United States)

    Pogorelov, A G; Matys, Iu V

    1990-01-01

    A rat small intestine mucosa is shown to accumulate significant amount of potassium and chloride. There was found a correlation between the content of these chemical elements and glycoprotein compartmentalization in goblet cell secret, brush border of enterocytes and a mucus layer. In this connection a role of mucus glycoproteins in membrane digestion is discussed. For preparation of samples the cryotechniques of electron microscopy are used.

  18. Radiation damage in soft X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.; Morin, C.; Li, L. [Department of Chemistry and Brockhouse Institute for Materials Research, McMaster University, Hamilton, ON, L8S 4M1 (Canada); Hitchcock, A.P. [Department of Chemistry and Brockhouse Institute for Materials Research, McMaster University, Hamilton, ON, L8S 4M1 (Canada)], E-mail: aph@mcmaster.ca; Scholl, A.; Doran, A. [Advanced Light Source, Berkeley Lab, Berkeley, CA 94720 (United States)

    2009-03-15

    The rates of chemical transformation by radiation damage of polystyrene (PS), poly(methyl methacrylate) (PMMA), and fibrinogen (Fg) in a X-ray photoemission electron microscope (X-PEEM) and in a scanning transmission X-ray microscope (STXM) have been measured quantitatively using synchrotron radiation. As part of the method of dose evaluation in X-PEEM, the characteristic (1/e) sampling depth of X-PEEM for polystyrene in the C 1s region was measured to be 4 {+-} 1 nm. Critical doses for chemical change as monitored by changes in the X-ray absorption spectra are 80 (12), 280 (40) and 1230 (180) MGy (1 MGy = 6.242*{rho} eV/nm{sup 3}, where {rho} is the polymer density in g/cm{sup 3}) at 300 eV photon energy for PMMA, Fg and PS, respectively. The critical dose for each material is comparable in X-PEEM and STXM and the values cited are thus the mean of the values determined by X-PEEM and STXM. C 1s, N 1s and O 1s spectroscopy of the damaged materials is used to gain insight into the chemical changes that soft X-rays induce in these materials.

  19. Localization of Hg and Pb in the palps, the digestive gland and the gills in Mytilus galloprovincialis (L.) using autometallography and X-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Dimitriadis, V.K.; Domouhtsidou, G.P.; Raftopoulou, E

    2003-10-01

    Palps are introduced as a new metal-storing organ in Mytilus galloprovincialis. - The intracellular localization of heavy metals using autometallography (AMG) and X-ray microanalysis was studied in the palps, the digestive gland and the gills of mussels Mytilus galloprovincialis, after an experimental exposure to 0.1 mg l{sup -1} of Hg and 0.1 mg l{sup -1} of Pb, for 30 and 60 days. In the examined tissues, autometallographical black silver deposits (BSD) were localized mainly in the residual bodies and heterolysosomes of the digestive cells, as well as in the dense bodies of the epithelial cells. Metal deposition after Hg exposure was much more abundant compared to Pb exposure. Using X-ray microanalysis, Hg was traced on the BSD in all examined tissues, while Pb was not traced in these deposits. The results are discussed in comparison to previous results on long-term exposure to the same metals; in addition, the palps are introduced as a new metal storing organ and, finally, the use of X-ray microanalysis under a scanning electron microscope in order to enhance the specificity of AMG is suggested.

  20. In situ hard X-ray microscopy of self-assembly in colloidal suspensions

    NARCIS (Netherlands)

    Byelov, D.; Meijer, J.M.; Snigireva, I.; Snigirev, A.; Rossi, L.; van den Pol, E.; Kuijk, A.; Philipse, A.P.; Imhof, A.; van Blaaderen, A.; Vroege, G.J.; Petukhov, A.V.

    2013-01-01

    An experimental setup combining full-field transmission X-ray microscopy (TXM) and microradian X-ray diffraction (mradXRD) is tested for the in situ study of self-organization of colloidal dispersions of anisotropic particles. Averaged structural information of the samples is determined by mradXRD

  1. In-situ scanning transmission X-ray microscopy of catalytic materials under reaction conditions

    NARCIS (Netherlands)

    de Smit, E.; Creemer, J.F.; Zandbergen, H.W.; Weckhuysen, B.M.; de Groot, F.M.F.

    2009-01-01

    In-situ Scanning X-ray Transmission Microscopy (STXM) allows the measurement of the soft X-ray absorption spectra with 10 to 30 nm spatial resolution under realistic reaction conditions. We show that STXM-XAS in combination with a micromachined nanoreactor can image a catalytic system under relevant

  2. Generation of apodized X-ray illumination and its application to scanning and diffraction microscopy.

    Science.gov (United States)

    Khakurel, Krishna P; Kimura, Takashi; Nakamori, Hiroki; Goto, Takumi; Matsuyama, Satoshi; Sasaki, Tomoya; Takei, Masashi; Kohmura, Yoshiki; Ishikawa, Tetsuya; Yamauchi, Kazuto; Nishino, Yoshinori

    2017-01-01

    X-ray science has greatly benefited from the progress in X-ray optics. Advances in the design and the manufacturing techniques of X-ray optics are key to the success of various microscopic and spectroscopic techniques practiced today. Here the generation of apodized X-ray illumination using a two-stage deformable Kirkpatrick-Baez mirror system is presented. Such apodized illumination is marked by the suppression of the side-lobe intensities of the focused beam. Thus generated apodized illumination was employed to improve the image quality in scanning X-ray fluorescence microscopy. Imaging of a non-isolated object by coherent X-ray diffractive imaging with apodized illumination in a non-scanning mode is also presented.

  3. Application of X-ray synchrotron microscopy instrumentation in biology

    Energy Technology Data Exchange (ETDEWEB)

    Gasperini, F. M. [Medical Science Program, Fluminense Federal Univ., Niteroi (Brazil); Pereira, G. R. [Dept. of Metallurgical and Materials Engineering, Federal Univ. of Rio de Janeiro (Brazil); Granjeiro, J. M. [Molecular and Cell Biology Dept., Fluminense Federal Univ., Niteroi, Rio de Janeiro (Brazil); Calasans-Maia, M. D. [Oral Surgery Dept., Fluminense Federal Univ., Niteroi, Rio de Janeiro (Brazil); Rossi, A. M. [Biomaterials Laboratory, Brazilian Center of Physics Research, Rio de Janeiro (Brazil); Perez, C. A. [Brazilian Synchrotron Laboratory, Campinas, Sao Paulo (Brazil); Lopes, R. T.; Lima, I. [Nuclear Engineering Laboratory, Federal Univ. of Rio de Janeiro (Brazil)

    2011-07-01

    X-ray micro-fluorescence imaging technique has been used as a significant tool in order to investigate minerals contents in some kinds of materials. The aim of this study was to evaluate the elemental distribution of calcium and zinc in bone substitute materials (nano-hydroxyapatite spheres) and cortical bones through X-Ray Micro-fluorescence analysis with the increment of Synchrotron Radiation in order to evaluate the characteristics of the newly formed bone and its interface, the preexisting bone and biomaterials by the arrangement of collagen fibers and its birefringence. The elemental mapping was carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo, Brazil working at D09-XRF beam line. Based on this study, the results suggest that hydroxyapatite-based biomaterials are biocompatible, promote osteo-conduction and favored bone repair. (authors)

  4. Scanning electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1998-01-01

    Scanning Electron Microscopy provides a description of the physics of electron-probe formation and of electron-specimen interations The different imaging and analytical modes using secondary and backscattered electrons, electron-beam-induced currents, X-ray and Auger electrons, electron channelling effects, and cathodoluminescence are discussed to evaluate specific contrasts and to obtain quantitative information

  5. Bulk sensitive hard x-ray photoemission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Patt, M., E-mail: m.patt@fz-juelich.de; Wiemann, C. [Peter Grünberg Institute (PGI-6) and JARA-FIT, Research Center Jülich, D-52425 Jülich (Germany); Weber, N.; Escher, M.; Merkel, M. [Focus GmbH, Neukirchner Str. 2, D-65510 Hünstetten (Germany); Gloskovskii, A.; Drube, W. [DESY Photon Science, Deutsches Elektronen-Synchrotron, D-22603 Hamburg (Germany); Schneider, C. M. [Peter Grünberg Institute (PGI-6) and JARA-FIT, Research Center Jülich, D-52425 Jülich (Germany); Fakultät f. Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, D-47048 Duisburg (Germany)

    2014-11-15

    Hard x-ray photoelectron spectroscopy (HAXPES) has now matured into a well-established technique as a bulk sensitive probe of the electronic structure due to the larger escape depth of the highly energetic electrons. In order to enable HAXPES studies with high lateral resolution, we have set up a dedicated energy-filtered hard x-ray photoemission electron microscope (HAXPEEM) working with electron kinetic energies up to 10 keV. It is based on the NanoESCA design and also preserves the performance of the instrument in the low and medium energy range. In this way, spectromicroscopy can be performed from threshold to hard x-ray photoemission. The high potential of the HAXPEEM approach for the investigation of buried layers and structures has been shown already on a layered and structured SrTiO{sub 3} sample. Here, we present results of experiments with test structures to elaborate the imaging and spectroscopic performance of the instrument and show the capabilities of the method to image bulk properties. Additionally, we introduce a method to determine the effective attenuation length of photoelectrons in a direct photoemission experiment.

  6. Alternative matrix formers for nanosuspension solidification: Dissolution performance and X-ray microanalysis as an evaluation tool for powder dispersion.

    Science.gov (United States)

    Van Eerdenbrugh, Bernard; Froyen, Ludo; Van Humbeeck, Jan; Martens, Johan A; Augustijns, Patrick; Van Den Mooter, Guy

    2008-11-15

    Four alternative matrix formers [Avicel PH101, Fujicalin (CaHPO(4)), Aerosil 200 (SiO(2)) and Inutec SP1] were evaluated for their capability in preserving rapid dissolution after spray-drying of nanosuspensions. Model drug compounds selected were cinnarizine (CIN), itraconazole (ITR) and phenylbutazone (PHB) as they showed a decrease in dissolution rate upon spray-drying in the absence of additional matrix formers, yielding release values after 5min of dissolution (release(5min)) of 57.7+/-1.0% (CIN), 56.3+/-3.8% (ITR) and 67.4+/-1.3% (PHB). Compared to the situation without matrix former inclusion, the performance of Avicel PH101 was good for CIN (release(5min)=90.9+/-7.7%), intermediate for PHB (release(5min)=81.0+/-6.4%) and poor for ITR (release(5min)=42.1+/-4.2%). For Fujicalin, intermediate (PHB: release(5min)=87.7+/-3.0%) or poor (CIN: release(5min)=66.1+/-3.4%; ITR: release(5min)=55.9+/-5.2%) performance was seen. Results for Aerosil 200 were good for all compounds (CIN: release(5min)=91.5+/-2.5%; ITR: release(5min)=83.8+/-3.4%; PHB: release(5min)=95.5+/-2.4%), indicating that the large specific surface area was in this case translated into good matrix forming capabilities. Finally, the best results were obtained for Inutec SP1 (CIN: release(5min)=88.7+/-1.2%; ITR: release(5min)=93.4+/-2.4%; PHB: release(5min)=101.3+/-4.9%). Except for Avicel PH101, Cl-maps from X-ray microanalysis of the itraconazole powders supported the hypothesis that better dispersion of drug in the powders results in faster dissolution.

  7. Correcting lateral chromatic aberrations in non-monochromatic X-ray microscopy

    Science.gov (United States)

    Falch, Ken Vidar; Detlefs, Carsten; Di Michiel, Marco; Snigireva, Irina; Snigirev, Anatoly; Mathiesen, Ragnvald H.

    2016-08-01

    Lateral chromatic aberration in microscopy based on refractive optics may be reduced significantly by adjustments to the illumination scheme. By taking advantage of a broadened bandwidth illumination, the proposed scheme could open for x-ray microscopy with spatial resolution in the range 150-200 nm at millisecond frame rates. The scheme is readily implemented and is achievable using only standard refractive x-ray lenses, which has the advantage of high efficiency. It also maximizes the transmission and removes the spatial filtering effects associated with absorption in x-ray lenses.

  8. Studying Nanoscale Magnetism and its Dynamics with Soft X-ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mccall, Monnikue M; Fischer, Peter

    2008-05-01

    Magnetic soft X-ray microscopy allows for imaging magnetic structures at a spatial resolution down to 15nm and a time resolution in the sub-100ps regime. Inherent elemental specificity can be used to image the magnetic response of individual components such as layers in multilayered systems. This review highlights current achievements and discusses the future potential of magnetic soft X-ray microscopy at fsec X-ray sources where snapshot images of ultrafast spin dynamics with a spatial resolution below 10nm will become feasible.

  9. Mapping cellular magnesium using X-ray microfluorescence and atomic force microscopy

    OpenAIRE

    2010-01-01

    Magnesium is the most abundant intracellular divalent cation. We present an innovative experimental approach to localizing intracellular magnesium that combines elemental and morphological information from individual cells with high-resolution spatial information. Integration of information from scanning fluorescence X-ray microscopy with information from atomic force microscopy was used to generate a magnesium concentration map and to determine the X-ray linear absorption coefficient map wit...

  10. Application possibilities of several modern methods of microscopy and microanalysis in forensic science field

    Science.gov (United States)

    Kotrly, Marek; Turkova, Ivana

    2011-06-01

    The methods of optical and electron microscopy and microanalysis are the linchpin of forensic inorganic analysis. However, their capacity is limited as for the exact identification of pigments and colour layers, and therefore it is essential that they be complemented by other methods of phase microanalysis - powder X-ray microdiffraction (micro pXRD) and FTIR in transmission mode. The classic way of sample division for different methods is not suitable with regard to the inhomogeneity of the sequence of strata. That is why a method was tested that would allow performance of optical microscopy, SEM/EDS(WDS), micro pXRD and FTIR in a nondestructive manner, from an identical spot of a single fragment. The solution can be polished sections - embedded samples and microtome sections. Conductive zerobackground single-crystal silicon plates were developed and tested for sample fixation in SEM, micro pXRD and transmission FTIR. Methods using a focused ion beam - FIB have recently gained importance in the field of electron microscopy. In the forensic sphere they can be employed in examinations of metal materials, technical analyses of documents, post-blast and gunshot residues.

  11. Combining operando synchrotron X-ray tomographic microscopy and scanning X-ray diffraction to study lithium ion batteries

    Science.gov (United States)

    Pietsch, Patrick; Hess, Michael; Ludwig, Wolfgang; Eller, Jens; Wood, Vanessa

    2016-01-01

    We present an operando study of a lithium ion battery combining scanning X-ray diffraction (SXRD) and synchrotron radiation X-ray tomographic microscopy (SRXTM) simultaneously for the first time. This combination of techniques facilitates the investigation of dynamic processes in lithium ion batteries containing amorphous and/or weakly attenuating active materials. While amorphous materials pose a challenge for diffraction techniques, weakly attenuating material systems pose a challenge for attenuation-contrast tomography. Furthermore, combining SXRD and SRXTM can be used to correlate processes occurring at the atomic level in the crystal lattices of the active materials with those at the scale of electrode microstructure. To demonstrate the benefits of this approach, we investigate a silicon powder electrode in lithium metal half-cell configuration. Combining SXRD and SRXTM, we are able to (i) quantify the dissolution of the metallic lithium electrode and the expansion of the silicon electrode, (ii) better understand the formation of the Li15Si4 phase, and (iii) non-invasively probe kinetic limitations within the silicon electrode. A simple model based on the 1D diffusion equation allows us to qualitatively understand the observed kinetics and demonstrates why high-capacity electrodes are more prone to inhomogeneous lithiation reactions. PMID:27324109

  12. X-ray dense cellular inclusions in the cells of the green alga Chlamydomonas reinhardtii as seen by soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stead, A.D.; Ford, T.W.; Page, A.M. [Univ. of London (United Kingdom); Brown, J.T.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Soft x-rays, having a greater ability to penetrate biological material than electrons, have the potential for producing images of intact, living cells. In addition, by using the so-called {open_quotes}water window{close_quotes} area of the soft x-ray spectrum, a degree of natural contrast is introduced into the image due to differential absorption of the wavelengths by compounds with a high carbon content compared to those with a greater oxygen content. The variation in carbon concentration throughout a cell therefore generates an image which is dependent upon the carbon density within the specimen. Using soft x-ray contact microscopy the authors have previously examined the green alga Chlamydomonas reinhardtii, and the most prominent feature of the cells are the numerous x-ray absorbing spheres, But they were not seen by conventional transmission electron microscopy. Similar structures have also been reported by the Goettingen group using their cryo transmission x-ray microscope at BESSY. Despite the fact that these spheres appear to occupy up to 20% or more of the cell volume when seen by x-ray microscopy, they are not visible by transmission electron microscopy. Given the difficulties and criticisms associated with soft x-ray contact microscopy, the present study was aimed at confirming the existence of these cellular inclusions and learning more of their possible chemical composition.

  13. Quantitative x-ray magnetic circular dichroism mapping with high spatial resolution full-field magnetic transmission soft x-ray spectro-microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, MacCallum J. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California, Berkeley, California 94720 (United States); Agostino, Christopher J. [Physics Department, University of California, Berkeley, California 94720 (United States); National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); N' Diaye, Alpha T. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Chen, Gong [National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Im, Mi-Young [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Emerging Materials Science, Daegu Gyeongbuk Institute of Science and Technology, Daegu 711-873 (Korea, Republic of); Fischer, Peter, E-mail: PJFischer@lbl.gov [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California, Santa Cruz, California 94056 (United States)

    2015-05-07

    The spectroscopic analysis of X-ray magnetic circular dichroism (XMCD), which serves as strong and element-specific magnetic contrast in full-field magnetic transmission soft x-ray microscopy, is shown to provide information on the local distribution of spin (S) and orbital (L) magnetic moments down to a spatial resolution of 25 nm limited by the x-ray optics used in the x-ray microscope. The spatially resolved L/S ratio observed in a multilayered (Co 0.3 nm/Pt 0.5 nm) × 30 thin film exhibiting a strong perpendicular magnetic anisotropy decreases significantly in the vicinity of domain walls, indicating a non-uniform spin configuration in the vertical profile of a domain wall across the thin film. Quantitative XMCD mapping with x-ray spectro-microscopy will become an important characterization tool for systems with topological or engineered magnetization inhomogeneities.

  14. Dark-field X-ray microscopy for multiscale structural characterization

    DEFF Research Database (Denmark)

    Simons, Hugh; King, A.; Ludwig, W.

    2015-01-01

    Many physical and mechanical properties of crystalline materials depend strongly on their internal structure, which is typically organized into grains and domains on several length scales. Here we present dark-field X-ray microscopy; a non-destructive microscopy technique for the three-dimensiona......Many physical and mechanical properties of crystalline materials depend strongly on their internal structure, which is typically organized into grains and domains on several length scales. Here we present dark-field X-ray microscopy; a non-destructive microscopy technique for the three...... of the interactions between crystalline elements is a key step towards the formulation and validation of multiscale models that account for the entire heterogeneity of a material. Furthermore, dark-field X-ray microscopy is well suited to applied topics, where the structural evolution of internal nanoscale elements...

  15. X-ray imaging microscopy at 25 keV with Fresnel zone plate optics

    CERN Document Server

    Awaji, M; Takeuchi, A; Takano, H; Kamijo, N; Tamura, S; Yasumoto, M

    2001-01-01

    X-ray imaging microscopy with a sputtered-sliced Fresnel zone plate (SS-FZP) has been developed at an X-ray energy of 25 keV. Objects were imaged in transmission with the SS-FZP as an objective with a magnification of 10.2 times, and detected with a X-ray image sensor. The performance of the imaging microscope has been tested with a gold mesh and a resolution test pattern at an undulator beamline 47XU of SPring-8. The resolution test patterns up to 0.5 mu m line-and-space structures have been resolved.

  16. Ptychography: Pushing the limits of X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fromm, Cayla [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-23

    Ptychography is an advanced diffraction based imaging technique that can achieve resolution of 5 nm, and below. It is done by scanning a sample through a beam of focused x-rays using discrete yet overlapping scan steps. Scattering data is collected on a CCD camera, and the phase of the scattered light is reconstructed with sophisticated iterative algorithms. Because the experimental setup is similar, ptychography setups can be created by retrofitting existing STXM beam lines with new hardware. The other challenge comes in the reconstruction of the collected scattering images. Scattering data must be adjusted and packaged with experimental parameters to calibrate the reconstruction software. The necessary pre-processing of data prior to reconstruction is unique to each beamline setup, and even the optical alignments used on that particular day. Pre-processing software must be developed to be flexible and efficient in order to allow experimenters appropriate control and freedom in the analysis of their hard-won data. This paper will describe the implementation of pre-processing software which successfully connects data collection steps to reconstruction steps, letting the user accomplish accurate and reliable ptychography.

  17. In-situ scanning transmission X-ray microscopy of catalytic materials under reaction conditions

    OpenAIRE

    E. Smit; Creemer, J.F.; Zandbergen, H. W.; Weckhuysen, B. M.; Groot, F.M.F. de

    2009-01-01

    In-situ Scanning X-ray Transmission Microscopy (STXM) allows the measurement of the soft X-ray absorption spectra with 10 to 30 nm spatial resolution under realistic reaction conditions. We show that STXM-XAS in combination with a micromachined nanoreactor can image a catalytic system under relevant reaction conditions, and provide detailed information on the morphology and composition of the catalyst material. The nanometer resolution combined with powerful chemical speciation by XAS and the...

  18. Electro-deposition of Cu studied with in situ electrochemical scanning transmission x-ray microscopy

    Science.gov (United States)

    Hitchcock, A. P.; Qin, Z.; Rosendahl, S. M.; Lee, V.; Reynolds, M.; Hosseinkhannazer, H.

    2016-01-01

    Soft X-ray scanning transmission X-ray microscopy (STXM) was used to investigate Cu deposition onto, and stripping from a Au surface. Cu 2p spectromicroscopy was used to analyze initial and final states (ex situ processing) and follow the processes in situ. The in situ experiments were carried out using a static electrochemical cell with an electrolyte layer thickness of ˜1 μm. A new apparatus for in situ electrochemical STXM is described.

  19. 2nd International Multidisciplinary Microscopy and Microanalysis Congress

    CERN Document Server

    Oral, Ahmet; Ozer, Mehmet

    2015-01-01

    The 2nd International Multidisciplinary Microscopy and Microanalysis Congress & Exhibition (InterM 2014) was held on 16–19 October 2014 in Oludeniz, Fethiye/ Mugla, Turkey. The aim of the congress was to gather scientists from various branches and discuss the latest improvements in the field of microscopy. The focus of the congress has been widened in an "interdisciplinary" manner, so as to allow all scientists working on several related subjects to participate and present their work. These proceedings include 33 peer-reviewed technical papers, submitted by leading academic and research institutions from over 17 countries and representing some of the most cutting-edge research available. The papers were presented at the congress in the following sessions: ·         Applications of Microscopy in the Physical Sciences ·         Applications of Microscopy in the Biological Sciences.

  20. High-resolution ab initio Three-dimensional X-ray Diffraction Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, H N; Barty, A; Marchesini, S; Noy, A; Cui, C; Howells, M R; Rosen, R; He, H; Spence, J H; Weierstall, U; Beetz, T; Jacobsen, C; Shapiro, D

    2005-08-19

    Coherent X-ray diffraction microscopy is a method of imaging non-periodic isolated objects at resolutions only limited, in principle, by the largest scattering angles recorded. We demonstrate X-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the 3D diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a non-periodic object. We also construct 2D images of thick objects with infinite depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution using X-ray undulator radiation, and establishes the techniques to be used in atomic-resolution ultrafast imaging at X-ray free-electron laser sources.

  1. Synchrotron X-ray microscopy and spectroscopy analysis of iron in hemochromatosis liver and intestines

    Energy Technology Data Exchange (ETDEWEB)

    Ko, J .Y. Peter; Sham, Tsun-Kong; Chakrabarti, Subrata; Adams, Paul C.; (UWO)

    2009-12-01

    Hemochromatosis is a genetic disorder that causes body to store excess iron in organs such as heart or liver. Distribution of iron, as well as copper, zinc and calcium, and chemical identity of iron in hemochromatosis liver and intestine were investigated by X-ray microprobe experiments, which consist of X-ray microscopy and micro-X-ray absorption fine structure. Our results show that iron concentration in hemochromatosis liver tissue is high, while much less Fe is found in intestinal tissue. Moreover, chemical identity of Fe in hemochromatosis liver can be identified. X-ray microprobe experiments allows for examining elemental distribution at an excellent spatial resolution. Moreover, chemical identity of element of interest can be obtained.

  2. Synchrotron X-ray microscopy and spectroscopy analysis of iron in hemochromatosis liver and intestines

    Science.gov (United States)

    Ko, J. Y. Peter; Sham, Tsun-Kong; Chakrabarti, Subrata; Adams, Paul C.

    2009-11-01

    Hemochromatosis is a genetic disorder that causes body to store excess iron in organs such as heart or liver. Distribution of iron, as well as copper, zinc and calcium, and chemical identity of iron in hemochromatosis liver and intestine were investigated by X-ray microprobe experiments, which consist of X-ray microscopy and micro-X-ray absorption fine structure. Our results show that iron concentration in hemochromatosis liver tissue is high, while much less Fe is found in intestinal tissue. Moreover, chemical identity of Fe in hemochromatosis liver can be identified. X-ray microprobe experiments allows for examining elemental distribution at an excellent spatial resolution. Moreover, chemical identity of element of interest can be obtained.

  3. Scanning tunneling microscopy studies of thin foil x-ray mirrors

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Besenbacher, Flemming; Garnaes, Jorgen;

    1990-01-01

    In this paper scanning tunneling microscopy (STM) measurements of x-ray mirrors are presented. The x-ray mirrors are 0.3 mm thick dip-lacquered aluminum foils coated with gold by evaporation, as well as state-of-the-art polished surfaces coated with gold, platinum, or iridium. The measurements....... The results can be used as a guide when selecting the best coating process in the production of x-ray mirrors....... that the microroughness depends on the thickness of the gold layer. The roughness is smallest (~7 to 9 Å) for gold layers between ~100 and ~250Å, and it becomes significantly greater (~10 to 15Å) for gold layers thicker than ~350 Å. With a few exceptions the STM measurements agree well with recent x-ray studies...

  4. Full-field hard x-ray microscopy with interdigitated silicon lenses

    CERN Document Server

    Simons, Hugh; Michael-Lindhard, Jonas; Jensen, Flemming; Hansen, Ole; Detlefs, Carsten; Poulsen, Henning Friis

    2015-01-01

    Full-field x-ray microscopy using x-ray objectives has become a mainstay of the biological and materials sciences. However, the inefficiency of existing objectives at x-ray energies above 15 keV has limited the technique to weakly absorbing or two-dimensional (2D) samples. Here, we show that significant gains in numerical aperture and spatial resolution may be possible at hard x-ray energies by using silicon-based optics comprising 'interdigitated' refractive silicon lenslets that alternate their focus between the horizontal and vertical directions. By capitalizing on the nano-manufacturing processes available to silicon, we show that it is possible to overcome the inherent inefficiencies of silicon-based optics and interdigitated geometries. As a proof-of-concept of Si-based interdigitated objectives, we demonstrate a prototype interdigitated lens with a resolution of ~255 nm at 17 keV.

  5. Electromigration in integrated circuit interconnects studied by X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, G. E-mail: gschnei1@gwdg.de; Denbeaux, G.; Anderson, E.; Bates, W.; Salmassi, F.; Nachimuthu, P.; Pearson, A.; Richardson, D.; Hambach, D.; Hoffmann, N.; Hasse, W.; Hoffmann, K

    2003-01-01

    To study mass transport phenomena in advanced microelectronic devices with X-rays requires penetration of dielectric and Si layers up to 30 {mu}m thick. X-ray imaging at 1.8 keV photon energy provides a high amplitude contrast between Cu or Al interconnects and dielectric layers and can penetrate through the required thickness. To perform X-ray microscopy at 1.8 keV, a new Ru/Si multilayer was designed for the transmission X-ray microscope XM-1 installed at the Advanced Light Source in Berkeley. The mass flow in a passivated Cu interconnect was studied at current densities up to 10{sup 7} A/cm{sup 2}. In addition, we demonstrated the high material contrast from different elements in integrated circuits with a resolution of about 40 nm.

  6. Calibration Of A KrF Laser-Plasma Source For X-Ray Microscopy Applications

    Science.gov (United States)

    Turcu, I. C. E.; O'Neill, F.; Zammit, U.; Al-Hadithi, Y.; Eason, R. W.; Rogayski, A. M.; Hills, C. P. B.; Michette, A. G.

    1988-02-01

    Plasma X-ray sources for biological microscopy in the water-window have been produced by focusing tige 200 3, 50 ns Sprit q KrF laser onto carbon targets at irradiance between 2.2 x 10" W/cm4 and 3.7 x 10i3W/cm. Absolute measurements of X-ray production have been made using a calibrated, vacuum X-ray diode detector. A peak conversion efficiency . 10% is measured from KrF laseri)Tight tcto wate-window X-rays at 280 eV < hv < 530 eV for a target irradiance . 1 x x 10 W/cm'. Some measurements with gold and tungsten targets give conversion efficiencies 2$25% at a similar laser irradiance.

  7. Laboratory source based full-field x-ray microscopy at 9 keV

    Energy Technology Data Exchange (ETDEWEB)

    Fella, C.; Balles, A.; Wiest, W. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Zabler, S.; Hanke, R. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Fraunhofer Development Center X-Ray Technology (EZRT), Flugplatzstrasse 75, 90768 Fürth (Germany)

    2016-01-28

    In the past decade, hard x-ray transmission microscopy experienced tremendous developments. With the avail-ability of efficient Fresnel zone plates, even set-ups utilizing laboratory sources were developed [1]. In order to improve the performance of these x-ray microscopes, novel approaches to fabricate optical elements [2] and brighter x-ray tubes [3] are promising candidates. We are currently building a laboratory transmission x-ray microscope for 9.25 keV, using an electron impact liquid-metal-jet anode source. Up to now, the further elements of our setup are: a polycapillary condenser, a tungsten zone plate, and a scintillator which is optically coupled to a CMOS camera. However, further variations in terms of optical elements are intended. Here we present the current status of our work, as well as first experimental results.

  8. X-ray microscopy using reflection targets based on SEM with tungsten filament

    Science.gov (United States)

    Liu, Junbiao; Ma, Yutian; Zhao, Weixia; Niu, Geng; Chu, Mingzhang; Yin, Bohua; Han, Li; Liu, Baodong

    2016-10-01

    X-ray MicroandNano imaging is developed based on the conventional x-ray tomography, it can not only provide nondestructive testing with higher resolution measurement, but also be used to examine the material or the structure with low atomic number and low density. The source with micro-focal spot size is one of the key components of x-ray MicroandNano imaging. The focused electron beam from SEM bombarding the metal target can generate x-ray with ultra-small size. It is convenient to set up x-ray microscopy based on SEM for laboratory use. This paper describes a new x-ray microscopy using reflection targets based on FEI Quanta600 SEM with tungsten filament. The flat panel detector is placed outside of the vacuum chamber with 300μm thickness Be-window to isolate vacuum from the air. A stage with 3 DOFs is added to adjust the positions of the target, the SEM's sample stage is used to move sample. And the shape of target is designed as cone with 60° half cone angle to get the maximum x-ray dosage. The attenuation coefficient of Bewindow for x-ray is about 25%. Finally, the line pair card is used to evaluate the resolution and the result shows that the resolution of the system can receive less than 750nm, when the acceleration voltage is 30keV, the beam current is 160nA, the SEM working distance is 5mm and the acquisition time of the detector is 60s.

  9. Imaging nanoscale lattice variations by machine learning of x-ray diffraction microscopy data

    Science.gov (United States)

    Laanait, Nouamane; Zhang, Zhan; Schlepütz, Christian M.

    2016-09-01

    We present a novel methodology based on machine learning to extract lattice variations in crystalline materials, at the nanoscale, from an x-ray Bragg diffraction-based imaging technique. By employing a full-field microscopy setup, we capture real space images of materials, with imaging contrast determined solely by the x-ray diffracted signal. The data sets that emanate from this imaging technique are a hybrid of real space information (image spatial support) and reciprocal lattice space information (image contrast), and are intrinsically multidimensional (5D). By a judicious application of established unsupervised machine learning techniques and multivariate analysis to this multidimensional data cube, we show how to extract features that can be ascribed physical interpretations in terms of common structural distortions, such as lattice tilts and dislocation arrays. We demonstrate this ‘big data’ approach to x-ray diffraction microscopy by identifying structural defects present in an epitaxial ferroelectric thin-film of lead zirconate titanate.

  10. Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

    Energy Technology Data Exchange (ETDEWEB)

    Moffet, Ryan C.; Tivanski, Alexei V.; Gilles, Mary K.

    2011-01-20

    Scanning transmission x-ray microscopy (STXM) combines x-ray microscopy and near edge x-ray absorption fine structure spectroscopy (NEXAFS). This combination provides spatially resolved bonding and oxidation state information. While there are reviews relevant to STXM/NEXAFS applications in other environmental fields (and magnetic materials) this chapter focuses on atmospheric aerosols. It provides an introduction to this technique in a manner approachable to non-experts. It begins with relevant background information on synchrotron radiation sources and a description of NEXAFS spectroscopy. The bulk of the chapter provides a survey of STXM/NEXAFS aerosol studies and is organized according to the type of aerosol investigated. The purpose is to illustrate the current range and recent growth of scientific investigations employing STXM-NEXAFS to probe atmospheric aerosol morphology, surface coatings, mixing states, and atmospheric processing.

  11. In Depth Analyses of LEDs by a Combination of X-ray Computed Tomography (CT) and Light Microscopy (LM) Correlated with Scanning Electron Microscopy (SEM).

    Science.gov (United States)

    Meyer, Jörg; Thomas, Christian; Tappe, Frank; Ogbazghi, Tekie

    2016-06-16

    In failure analysis, device characterization and reverse engineering of light emitting diodes (LEDs), and similar electronic components of micro-characterization, plays an important role. Commonly, different techniques like X-ray computed tomography (CT), light microscopy (LM) and scanning electron microscopy (SEM) are used separately. Similarly, the results have to be treated for each technique independently. Here a comprehensive study is shown which demonstrates the potentials leveraged by linking CT, LM and SEM. In depth characterization is performed on a white emitting LED, which can be operated throughout all characterization steps. Major advantages are: planned preparation of defined cross sections, correlation of optical properties to structural and compositional information, as well as reliable identification of different functional regions. This results from the breadth of information available from identical regions of interest (ROIs): polarization contrast, bright and dark-field LM images, as well as optical images of the LED cross section in operation. This is supplemented by SEM imaging techniques and micro-analysis using energy dispersive X-ray spectroscopy.

  12. An introduction to three-dimensional X-ray diffraction microscopy

    DEFF Research Database (Denmark)

    Poulsen, Henning Friis

    2012-01-01

    Three-dimensional X-ray diffraction microscopy is a fast and nondestructive structural characterization technique aimed at studies of the individual crystalline elements (grains or subgrains) within millimetre-sized polycrystalline specimens. It is based on two principles: the use of highly penet....... © 2012 International Union of Crystallography Printed in Singapore-all rights reserved....

  13. Visualization of magnetic dipolar interaction based on scanning transmission X-ray microscopy

    Science.gov (United States)

    Ohtori, Hiroyuki; Iwano, Kaoru; Mitsumata, Chiharu; Takeichi, Yasuo; Yano, Masao; Kato, Akira; Miyamoto, Noritaka; Shoji, Tetsuya; Manabe, Akira; Ono, Kanta

    2014-04-01

    Using scanning transmission X-ray microscopy (STXM), in this report we visualized the magnetic dipolar interactions in nanocrystalline Nd-Fe-B magnets and imaged their magnetization distributions at various applied fields. We calculated the magnetic dipolar interaction by analyzing the interaction between the magnetization at each point and those at the other points on the STXM image.

  14. Application of X-ray microscopy in food science investigation of high pressure affected bacterial spores

    Science.gov (United States)

    Mönch, Susanne; Heinz, Volker; Guttmann, Peter; Knorr, Dietrich

    2000-05-01

    Using the Göttingen transmission X-ray microscope at BESSY the effect of different pressure and temperature levels during the high hydrostatic pressure (HP) treatment was investigated. At 150 MPa and temperatures up to 50 °C the triggering of germination was observed by standard microbiological methods with Bacillus subtilis spores. Increasing the temperature to 70 °C at the same pressure level killed the spores without any indication of germination. By X-ray microscopy images it could be shown that the typical disintegration of the protoplast is inhibited. This suggests that the enzymic reaction pathway is possibly affected under specific pressure temperature conditions.

  15. Standing-wave excited soft x-ray photoemission microscopy: application to Co microdot magnetic arrays

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Alexander; Kronast, Florian; Papp, Christian; Yang, See-Hun; Cramm, Stefan; Krug, Ingo P.; Salmassi, Farhad; Gullikson, Eric M.; Hilken, Dawn L.; Anderson, Erik H.; Fischer, Peter; Durr, Hermann A.; Schneider, Claus M.; Fadley, Charles S.

    2010-10-29

    We demonstrate the addition of depth resolution to the usual two-dimensional images in photoelectron emission microscopy (PEEM), with application to a square array of circular magnetic Co microdots. The method is based on excitation with soft x-ray standing-waves generated by Bragg reflection from a multilayer mirror substrate. Standing wave is moved vertically through sample simply by varying the photon energy around the Bragg condition. Depth-resolved PEEM images were obtained for all of the observed elements. Photoemission intensities as functions of photon energy were compared to x-ray optical calculations in order to quantitatively derive the depth-resolved film structure of the sample.

  16. In-situ Scanning Transmission X-ray Microscopy of catalytic materials under reaction conditions

    Science.gov (United States)

    de Smit, Emiel; Creemer, J. Fredrik; Zandbergen, Henny W.; Weckhuysen, Bert M.; de Groot, Frank M. F.

    2009-11-01

    In-situ Scanning X-ray Transmission Microscopy (STXM) allows the measurement of the soft X-ray absorption spectra with 10 to 30 nm spatial resolution under realistic reaction conditions. We show that STXM-XAS in combination with a micromachined nanoreactor can image a catalytic system under relevant reaction conditions, and provide detailed information on the morphology and composition of the catalyst material. The nanometer resolution combined with powerful chemical speciation by XAS and the ability to image materials under realistic conditions opens up new opportunities to study many chemical processes.

  17. In-situ Scanning Transmission X-ray Microscopy of catalytic materials under reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Smit, Emiel de; Weckhuysen, Bert M; Groot, Frank M F de [Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands); Creemer, J Fredrik [DIMES-ECTM, Delft University of Technology, 2600 GB Delft (Netherlands); Zandbergen, Henny W, E-mail: e.desmit@uu.n [Kavli Institute of NanoScience, National Centre for High Resolution Electron Microscopy, Delft University of Technology, 2600 GA Delft (Netherlands)

    2009-11-15

    In-situ Scanning X-ray Transmission Microscopy (STXM) allows the measurement of the soft X-ray absorption spectra with 10 to 30 nm spatial resolution under realistic reaction conditions. We show that STXM-XAS in combination with a micromachined nanoreactor can image a catalytic system under relevant reaction conditions, and provide detailed information on the morphology and composition of the catalyst material. The nanometer resolution combined with powerful chemical speciation by XAS and the ability to image materials under realistic conditions opens up new opportunities to study many chemical processes.

  18. Transmission electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1997-01-01

    Transmission Electron Microscopy presents the theory of image and contrast formation, and the analytical modes in transmission electron microscopy. The principles of particle and wave optics of electrons are described. Electron-specimen interactions are discussed for evaluating the theory of scattering and phase contrast. Also discussed are the kinematical and dynamical theories of electron diffraction and their applications for crystal-structure analysis and imaging of lattices and their defects. X-ray micronanalysis and electron energy-loss spectroscopy are treated as analytical methods. Specimen damage and contamination by electron irradiation limits the resolution for biological and some inorganic specimens. This fourth edition includes discussion of recent progress, especially in the area of Schottky emission guns, convergent-beam electron diffraction, electron tomography, holography and the high resolution of crystal lattices.

  19. Stereo soft x-ray microscopy and elemental mapping of hematite and clay suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Gleber, S.-C.; Thieme, J.; Chao, W.; Fischer, P.

    2008-09-01

    The spatial arrangements of hematite particles within aqueous soil and clay samples are investigated with soft X-ray microscopy, taking advantage of the elemental contrast at the Fe-L edge around E = 707 eV. In combination with stereo microscopy, information about spatial arrangements are revealed and correlated to electrostatic interactions of the different mixtures. Manipulation of a sample mounted to the microscope is possible and particles added while imaging can be detected.

  20. Signal-to-noise and radiation exposure considerations in conventional and diffraction x-ray microscopy.

    Science.gov (United States)

    Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; Nelson, Johanna; Shapiro, David; Stewart, Andrew; Turner, Joshua; Jacobsen, Chris

    2009-08-03

    Using a signal-to-noise ratio estimation based on correlations between multiple simulated images, we compare the dose efficiency of two soft x-ray imaging systems: incoherent brightfield imaging using zone plate optics in a transmission x-ray microscope (TXM), and x-ray diffraction microscopy (XDM) where an image is reconstructed from the far-field coherent diffraction pattern. In XDM one must computationally phase weak diffraction signals; in TXM one suffers signal losses due to the finite numerical aperture and efficiency of the optics. In simulations with objects representing isolated cells such as yeast, we find that XDM has the potential for delivering equivalent resolution images using fewer photons. This can be an important advantage for studying radiation-sensitive biological and soft matter specimens.

  1. Cryogenic x-ray diffraction microscopy utilizing high-pressure cryopreservation.

    Science.gov (United States)

    Lima, Enju; Chushkin, Yuriy; van der Linden, Peter; Kim, Chae Un; Zontone, Federico; Carpentier, Philippe; Gruner, Sol M; Pernot, Petra

    2014-10-01

    We present cryo x-ray diffraction microscopy of high-pressure-cryofixed bacteria and report high-convergence imaging with multiple image reconstructions. Hydrated D. radiodurans cells were cryofixed at 200 MPa pressure into ∼10-μm-thick water layers and their unstained, hydrated cellular environments were imaged by phasing diffraction patterns, reaching sub-30-nm resolutions with hard x-rays. Comparisons were made with conventional ambient-pressure-cryofixed samples, with respect to both coherent small-angle x-ray scattering and the image reconstruction. The results show a correlation between the level of background ice signal and phasing convergence, suggesting that phasing difficulties with frozen-hydrated specimens may be caused by high-background ice scattering.

  2. Fracture mechanics by three-dimensional crack-tip synchrotron X-ray microscopy.

    Science.gov (United States)

    Withers, P J

    2015-03-06

    To better understand the relationship between the nucleation and growth of defects and the local stresses and phase changes that cause them, we need both imaging and stress mapping. Here, we explore how this can be achieved by bringing together synchrotron X-ray diffraction and tomographic imaging. Conventionally, these are undertaken on separate synchrotron beamlines; however, instruments capable of both imaging and diffraction are beginning to emerge, such as ID15 at the European Synchrotron Radiation Facility and JEEP at the Diamond Light Source. This review explores the concept of three-dimensional crack-tip X-ray microscopy, bringing them together to probe the crack-tip behaviour under realistic environmental and loading conditions and to extract quantitative fracture mechanics information about the local crack-tip environment. X-ray diffraction provides information about the crack-tip stress field, phase transformations, plastic zone and crack-face tractions and forces. Time-lapse CT, besides providing information about the three-dimensional nature of the crack and its local growth rate, can also provide information as to the activation of extrinsic toughening mechanisms such as crack deflection, crack-tip zone shielding, crack bridging and crack closure. It is shown how crack-tip microscopy allows a quantitative measure of the crack-tip driving force via the stress intensity factor or the crack-tip opening displacement. Finally, further opportunities for synchrotron X-ray microscopy are explored.

  3. Characterization of size-resolved urban haze particles collected in summer and winter at Taiyuan City, China using quantitative electron probe X-ray microanalysis

    Science.gov (United States)

    Geng, Hong; Jin, Chun-Song; Zhang, Dong-Peng; Wang, Shu-Rong; Xu, Xiao-Tian; Wang, Xu-Ran; Zhang, Yuan; Wu, Li; Ro, Chul-Un

    2017-07-01

    The aim of the study is to characterize the size-resolved urban haze particles and investigate their modification in morphology and composition in summer and winter using the semi-quantitative electron probe X-ray microanalysis (EPMA) based on both scanning and transmission electron microscopies equipped with ultrathin-window energy dispersive X-ray spectrometers (SEM-EDX and TEM-EDX). The haze and non-haze particles were collected through a seven-stage May cascade impactor on Dec. 29-30, 2009 and Jan. 8-9 and July 11-14, 2010 in Taiyuan, a typical inland city in the North China Plain. Approximately 3752 atmospheric particles in the size ranges of 4-2 μm, 2-1 μm, 1-0.5 μm, and 0.5-0.25 μm in aerodynamic diameter were measured and identified according to their secondary electron or TEM images and elemental atomic concentrations calculated through a Monte Carlo simulation program. Results show that on the haze days many reacted or aged mineral dust particles were encountered, in which the sulfate-containing ones outnumbered the nitrate-containing ones in the winter samples while it was on the contrary in the summer samples, suggesting different haze formation and evolution mechanisms in summer and winter. Furthermore, in the haze events (especially in summer), many CNOS-rich particles, likely mixtures of water-soluble organic carbon with (NH4)2SO4 or NH4HSO4, were observed not only in the submicron but also in the super-micron fractions. The simultaneous observation of the fresh and aged CNOS-rich particles in the same SEM or TEM images implied that the status and components of secondary particles were complicated and changeable. The significant increase of both elemental concentration ratios of [N]/[S] and [C]/[S] in the aged ones compared to the fresh ones indicated that NH4NO3 and secondary organic matter were likely absorbed onto (NH4)2SO4 or NH4HSO4 particles and mixed with them. K-rich, Fe-rich, and heavy metal-containing particles in TEM-EDX measurement

  4. X-ray intravital microscopy for functional imaging in rat hearts using synchrotron radiation coronary microangiography

    Energy Technology Data Exchange (ETDEWEB)

    Umetani, K. [Japan Synchrotron Radiation Research Institute, SPring-8, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Fukushima, K. [National Cerebral and Cardiovascular Center Hospital, Fujishirodai, Suita-shi, Osaka 565-8565 (Japan)

    2013-03-15

    An X-ray intravital microscopy technique was developed to enable in vivo visualization of the coronary, cerebral, and pulmonary arteries in rats without exposure of organs and with spatial resolution in the micrometer range and temporal resolution in the millisecond range. We have refined the system continually in terms of the spatial resolution and exposure time. X-rays transmitted through an object are detected by an X-ray direct-conversion type detector, which incorporates an X-ray SATICON pickup tube. The spatial resolution has been improved to 6 {mu}m, yielding sharp images of small arteries. The exposure time has been shortened to around 2 ms using a new rotating-disk X-ray shutter, enabling imaging of beating rat hearts. Quantitative evaluations of the X-ray intravital microscopy technique were extracted from measurements of the smallest-detectable vessel size and detection of the vessel function. The smallest-diameter vessel viewed for measurements is determined primarily by the concentration of iodinated contrast material. The iodine concentration depends on the injection technique. We used ex vivo rat hearts under Langendorff perfusion for accurate evaluation. After the contrast agent is injected into the origin of the aorta in an isolated perfused rat heart, the contrast agent is delivered directly into the coronary arteries with minimum dilution. The vascular internal diameter response of coronary arterial circulation is analyzed to evaluate the vessel function. Small blood vessels of more than about 50 {mu}m diameters were visualized clearly at heart rates of around 300 beats/min. Vasodilation compared to the control was observed quantitatively using drug manipulation. Furthermore, the apparent increase in the number of small vessels with diameters of less than about 50 {mu}m was observed after the vasoactive agents increased the diameters of invisible small blood vessels to visible sizes. This technique is expected to offer the potential for direct

  5. Investigation of nanoparticulate silicon as printed layers using scanning electron microscopy, transmission electron microscopy, X-ray absorption spectroscopy and X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Unuigbe, David M.; Harting, Margit; Jonah, Emmanuel O.; Britton, David T.; Nordlund, Dennis

    2017-08-21

    The presence of native oxide on the surface of silicon nanoparticles is known to inhibit charge transport on the surfaces. Scanning electron microscopy (SEM) studies reveal that the particles in the printed silicon network have a wide range of sizes and shapes. High-resolution transmission electron microscopy reveals that the particle surfaces have mainly the (111)- and (100)-oriented planes which stabilizes against further oxidation of the particles. X-ray absorption spectroscopy (XANES) and X-ray photoelectron spectroscopy (XPS) measurements at the O 1s-edge have been utilized to study the oxidation and local atomic structure of printed layers of silicon nanoparticles which were milled for different times. XANES results reveal the presence of the +4 (SiO2) oxidation state which tends towards the +2 (SiO) state for higher milling times. Si 2pXPS results indicate that the surfaces of the silicon nanoparticles in the printed layers are only partially oxidized and that all three sub-oxide, +1 (Si2O), +2 (SiO) and +3 (Si2O3), states are present. The analysis of the change in the sub-oxide peaks of the silicon nanoparticles shows the dominance of the +4 state only for lower milling times.

  6. Chemical State Mapping of Degraded B4C Control Rod Investigated with Soft X-ray Emission Spectrometer in Electron Probe Micro-analysis

    Science.gov (United States)

    Kasada, R.; Ha, Y.; Higuchi, T.; Sakamoto, K.

    2016-05-01

    B4C is widely used as control rods in light water reactors, such as the Fukushima Daiichi nuclear power plant, because it shows excellent neutron absorption and has a high melting point. However, B4C can melt at lower temperatures owing to eutectic interactions with stainless steel and can even evaporate by reacting with high-temperature steam under severe accident conditions. To reduce the risk of recriticality, a precise understanding of the location and chemical state of B in the melt core is necessary. Here we show that a novel soft X-ray emission spectrometer in electron probe microanalysis can help to obtain a chemical state map of B in a modeled control rod after a high-temperature steam oxidation test.

  7. In-situ scanning transmission X-ray microscopy of catalytic solids and related nanomaterials.

    Science.gov (United States)

    de Groot, Frank M F; de Smit, Emiel; van Schooneveld, Matti M; Aramburo, Luis R; Weckhuysen, Bert M

    2010-04-01

    The present status of in-situ scanning transmission X-ray microscopy (STXM) is reviewed, with an emphasis on the abilities of the STXM technique in comparison with electron microscopy. The experimental aspects and interpretation of X-ray absorption spectroscopy (XAS) are briefly introduced and the experimental boundary conditions that determine the potential applications for in-situ XAS and in-situ STXM studies are discussed. Nanoscale chemical imaging of catalysts under working conditions is outlined using cobalt and iron Fischer-Tropsch catalysts as showcases. In the discussion, we critically compare STXM-XAS and STEM-EELS (scanning transmission electron microscopy-electron energy loss spectroscopy) measurements and indicate some future directions of in-situ nanoscale imaging of catalytic solids and related nanomaterials.

  8. In-situ Scanning Transmission X-Ray Microscopy of Catalytic Solids and Related Nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    de Groot, F.; Smit, E; van Schooneveld, M; Aramburo, L; Weckhuysen, W

    2010-01-01

    The present status of in-situ scanning transmission X-ray microscopy (STXM) is reviewed, with an emphasis on the abilities of the STXM technique in comparison with electron microscopy. The experimental aspects and interpretation of X-ray absorption spectroscopy (XAS) are briefly introduced and the experimental boundary conditions that determine the potential applications for in-situ XAS and in-situ STXM studies are discussed. Nanoscale chemical imaging of catalysts under working conditions is outlined using cobalt and iron Fischer-Tropsch catalysts as showcases. In the discussion, we critically compare STXM-XAS and STEM-EELS (scanning transmission electron microscopy-electron energy loss spectroscopy) measurements and indicate some future directions of in-situ nanoscale imaging of catalytic solids and related nanomaterials.

  9. High-resolution x-ray photoemission electron microscopy at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Stammler, T.; Anders, S.; Padmore, H.A. [Lawrence Berkeley National Lab., CA (United States); Stoehr, J. [IBM Almaden Research Center, San Jose, CA (United States); Scheinfein, M. [Arizona State Univ., Tempe, AZ (United States). Dept. of Physics and Astronomy; Ade, H. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Physics

    1998-12-31

    X-ray Photoemission Electron Microscopy (X-PEEM) is a full-field imaging technique where the sample is illuminated by an x-ray beam and the photoemitted electrons are imaged on a screen by means of an electron optics. It therefore combines two well-established materials analysis techniques--photoemission electron microscopy (PEEM) and x-ray spectroscopy such as near edge x-ray absorption fine structure (NEXAFS) spectroscopy. This combination opens a wide field of new applications in materials research and has proven to be a powerful tool to investigate simultaneously topological, elemental, chemical state, and magnetic properties of surfaces, thin films, and multilayers at high spatial resolution. A new X-PEEM installed at the bend magnet beamline 7.3.1.1 at the Advanced Light Source (ALS) is designed for a spatial resolution of 20 nm and is currently under commissioning. An overview of the ongoing experimental program using X-PEEM in the field of materials research at the ALS is given by elemental and chemical bonding contrast imaging of hard disk coatings and sliders, field emission studies on diamond films as possible candidates for field-emission flat-panel displays, and the study of dewetting and decomposition phenomena of thin polymer blends and bilayers.

  10. Possibilities and Challenges of Scanning Hard X-ray Spectro-microscopy Techniques in Material Sciences

    Directory of Open Access Journals (Sweden)

    Andrea Somogyi

    2015-06-01

    Full Text Available Scanning hard X-ray spectro-microscopic imaging opens unprecedented possibilities in the study of inhomogeneous samples at different length-scales. It gives insight into the spatial variation of the major and minor components, impurities and dopants of the sample, and their chemical and electronic states at micro- and nano-meter scales. Measuring, modelling and understanding novel properties of laterally confined structures are now attainable. The large penetration depth of hard X-rays (several keV to several 10 keV beam energy makes the study of layered and buried structures possible also in in situ and in operando conditions. The combination of different X-ray analytical techniques complementary to scanning spectro-microscopy, such as X-ray diffraction, X-ray excited optical luminescence, secondary ion mass spectrometry (SIMS and nano-SIMS, provides access to optical characteristics and strain and stress distributions. Complex sample environments (temperature, pressure, controlled atmosphere/vacuum, chemical environment are also possible and were demonstrated, and allow as well the combination with other analysis techniques (Raman spectroscopy, infrared imaging, mechanical tensile devices, etc. on precisely the very same area of the sample. The use of the coherence properties of X-rays from synchrotron sources is triggering emerging experimental imaging approaches with nanometer lateral resolution. New fast analytical possibilities pave the way towards statistically significant studies at multi- length-scales and three dimensional tomographic investigations. This paper gives an overview of these techniques and their recent achievements in the field of material sciences.

  11. An expert system for chemical speciation of individual particles using low-Z particle electron probe X-ray microanalysis data.

    Science.gov (United States)

    Ro, Chul-Un; Kim, HyeKyeong; Van Grieken, René

    2004-03-01

    An electron probe X-ray microanalysis (EPMA) technique, using an energy-dispersive X-ray detector with an ultrathin window, designated a low-Z particle EPMA, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements, such as C, N, and O, as well as chemical elements that can be analyzed by conventional energy-dispersive EPMA, in individual particles. Since a data set is usually composed of data for several thousands of particles in order to make environmentally meaningful observations of real atmospheric aerosol samples, the development of a method that fully extracts chemical information contained in the low-Z particle EPMA data is important. An expert system that can rapidly and reliably perform chemical speciation from the low-Z particle EPMA data is presented. This expert system tries to mimic the logic used by experts and is implemented by applying macroprogramming available in MS Excel software. Its feasibility is confirmed by applying the expert system to data for various types of standard particles and a real atmospheric aerosol sample. By applying the expert system, the time necessary for chemical speciation becomes shortened very much and detailed information on particle data can be saved and extracted later if more information is needed for further analysis.

  12. Imaging interfacial micro- and nano-bubbles by scanning transmission soft X-ray microscopy.

    Science.gov (United States)

    Zhang, Lijuan; Zhao, Binyu; Xue, Lian; Guo, Zhi; Dong, Yaming; Fang, Haiping; Tai, Renzhong; Hu, Jun

    2013-05-01

    Synchrotron-based scanning transmission soft X-ray microscopy (STXM) with nanometer resolution was used to investigate the existence and behavior of interfacial gas nanobubbles confined between two silicon nitride windows. The observed nanobubbles of SF6 and Ne with diameters smaller than 2.5 µm were quite stable. However, larger bubbles became unstable and grew during the soft X-ray imaging, indicating that stable nanobubbles may have a length scale, which is consistent with a previous report using atomic force microscopy [Zhang et al. (2010), Soft Matter, 6, 4515-4519]. Here, it is shown that STXM is a promising technique for studying the aggregation of gases near the solid/water interfaces at the nanometer scale.

  13. X-ray microanalysis with transition edge sensors. The future of material analysis with scanning electron microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Hollerith, C.

    2006-07-05

    In current experiments and technical applications the demand for new and advanced concepts for the detection of radiation and particle is increasing. Low temperature detectors such as Transition Edge Sensors (TES) have been developed as ultrahigh-resolution radiation and particle detectors offering advantages in manifold applications. They were designed primarily for astrophysical experiments such as the dark matter search. In material analysis they have been introduced to revolutionize mass spectroscopy of biological molecules and Energy Dispersive X-ray Spectroscopy (EDS). EDS is the determination of the elemental constitution of samples in scanning electron microscopes (SEMs) with characteristic X-ray radiation excited by the electron beam. The use of TES detectors improves the EDS analysis of small volumes such as particles or thin layers. This is especially important for the semiconductor industry because of the continual shrinking of device size. Current structure sizes of 65 nm are already demanding new approaches in analytic methodology. In this thesis the introduction and improvement of a fully automated TES detector system in the industrial environment of a semiconductor failure analysis lab is described. This system, marketed under the trade name of 'Polaris' by the manufacturer, is based on a mechanical pulse tube cooler in combination with an adiabatic demagnetization refrigerator (ADR) for cooling the TES detector to its operating temperature. Several large improvements had to be made to the system during the total system integration. The energy resolution could be improved significantly thus enabling a better peak separation and the measurement of chemical shifts. Due to the small area of TES detectors compared with conventional EDS detectors the efficiency of the system proved to be too low for everyday use. A polycapillary X-ray lens was added to the system in order to solve this problem. The application of the lens, however, brought its

  14. Correlative Light and Scanning X-Ray Scattering Microscopy of Healthy and Pathologic Human Bone Sections

    OpenAIRE

    Giannini, C.; D. Siliqi; Bunk, O.; Beraudi, A.; Ladisa, M.; Altamura, D.; Stea, S.; Baruffaldi, F.

    2012-01-01

    Scanning small and wide angle X-ray scattering (scanning SWAXS) experiments were performed on healthy and pathologic human bone sections. Via crystallographic tools the data were transformed into quantitative images and as such compared with circularly polarized light (CPL) microscopy images. SWAXS and CPL images allowed extracting information of the mineral nanocrystalline phase embedded, with and without preferred orientation, in the collagen fibrils, mapping local changes at sub-osteon res...

  15. Small angle x-ray scattering and electron microscopy of nanoparticles formed in an electrical arc

    OpenAIRE

    Carvou, E; J. L. Le Garrec; Pérez, J.(University Autonoma Madrid, Department of Theoretical Physics, Madrid, Spain); J. Praquin; M. Djeddi; Mitchell, J.B.A.

    2013-01-01

    Small Angle X-ray Scattering has been used to characterize nanoparticles generated by electrical arcing between metallic (AgSnO2) electrodes. The particles are found to have diameters between 30 and 40 nm and display smooth surfaces suggesting that they are either in liquid form or have solidified from the liquid state. Particles collected around the electrodes were analyzed by Transmission Electron Microscopy and were seen to be much larger than those seen in the SAXS measurement, to be sphe...

  16. The amorphous Zn biomineralization at Naracauli stream, Sardinia: electron microscopy and X-ray absorption spectroscopy.

    Science.gov (United States)

    Medas, D; Lattanzi, P; Podda, F; Meneghini, C; Trapananti, A; Sprocati, A; Casu, M A; Musu, E; De Giudici, G

    2014-01-01

    An amorphous Zn biomineralization ("white mud"), occurring at Naracauli stream, Sardinia, in association with cyanobacteria Leptolyngbya frigida and diatoms, was investigated by electron microscopy and X-ray absorption spectroscopy. Preliminary diffraction analysis shows that the precipitate sampled on Naracauli stream bed is mainly amorphous, with some peaks ascribable to quartz and phyllosilicates, plus few minor unattributed peaks. Scanning electron microscopy analysis shows that the white mud, precipitated in association with a seasonal biofilm, is made of sheaths rich in Zn, Si, and O, plus filaments likely made of organic matter. Transmission electron microscopy analysis shows that the sheaths are made of smaller units having a size in the range between 100 and 200 nm. X-ray absorption near-edge structure and extended X-ray absorption fine structure data collected at the Zn K-edge indicate that the biomineral has a local structure similar to hemimorphite, a zinc sorosilicate. The differences of this biomineral with respect to the hydrozincite biomineralization documented about 3 km upstream in the same Naracauli stream may be related to either variations in the physicochemical parameters and/or different metabolic behavior of the involved biota.

  17. Scanning electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1985-01-01

    The aim of this book is to outline the physics of image formation, electron­ specimen interactions, imaging modes, the interpretation of micrographs and the use of quantitative modes "in scanning electron microscopy (SEM). lt forms a counterpart to Transmission Electron Microscopy (Vol. 36 of this Springer Series in Optical Sciences) . The book evolved from lectures delivered at the University of Münster and from a German text entitled Raster-Elektronenmikroskopie (Springer-Verlag), published in collaboration with my colleague Gerhard Pfefferkorn. In the introductory chapter, the principles of the SEM and of electron­ specimen interactions are described, the most important imaging modes and their associated contrast are summarized, and general aspects of eiemental analysis by x-ray and Auger electron emission are discussed. The electron gun and electron optics are discussed in Chap. 2 in order to show how an electron probe of small diameter can be formed, how the elec­ tron beam can be blanked at high fre...

  18. Quantitative 3D imaging of whole, unstained cells by using X-ray diffraction microscopy.

    Science.gov (United States)

    Jiang, Huaidong; Song, Changyong; Chen, Chien-Chun; Xu, Rui; Raines, Kevin S; Fahimian, Benjamin P; Lu, Chien-Hung; Lee, Ting-Kuo; Nakashima, Akio; Urano, Jun; Ishikawa, Tetsuya; Tamanoi, Fuyuhiko; Miao, Jianwei

    2010-06-22

    Microscopy has greatly advanced our understanding of biology. Although significant progress has recently been made in optical microscopy to break the diffraction-limit barrier, reliance of such techniques on fluorescent labeling technologies prohibits quantitative 3D imaging of the entire contents of cells. Cryoelectron microscopy can image pleomorphic structures at a resolution of 3-5 nm, but is only applicable to thin or sectioned specimens. Here, we report quantitative 3D imaging of a whole, unstained cell at a resolution of 50-60 nm by X-ray diffraction microscopy. We identified the 3D morphology and structure of cellular organelles including cell wall, vacuole, endoplasmic reticulum, mitochondria, granules, nucleus, and nucleolus inside a yeast spore cell. Furthermore, we observed a 3D structure protruding from the reconstructed yeast spore, suggesting the spore germination process. Using cryogenic technologies, a 3D resolution of 5-10 nm should be achievable by X-ray diffraction microscopy. This work hence paves a way for quantitative 3D imaging of a wide range of biological specimens at nanometer-scale resolutions that are too thick for electron microscopy.

  19. Organic Compounds in Silica Bodies of Rice Revealed by X-ray Microanalysis and Micro-infrared Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    MA Xue-long; FANG Jiang-yu

    2005-01-01

    To understand the possible mechanism controlling the formation of silicon bodies in higher plants, we need to know the nature of organic compounds associated with silicon bodies and induces silicon precipitation in plant cells. A new method was developed to isolate pure silicon body in fresh leaves of rice (Oryaa sativa L. Var. 297) at low temperature by grinding and centrifugation procedures, which avoided degradation of organic molecules induced by high temperature and strong oxidizing acids used in the traditional method. The energy dispersive X-ray spectrum under scanning electron microscope showed that there was a great amount of carbon in silicon bodies in addition to silicon and oxygen. Organic compounds intimately associated with silicon bodies were released by treatment with HF solution. Analysis of the organic compounds by micro-infrared spectroscopy revealed the presence of polyphenol and polysaccharide and a little protein.

  20. Study of Interactions Between Microbes and Minerals by Scanning Transmission X-Ray Microscopy (STXM)

    Energy Technology Data Exchange (ETDEWEB)

    Benzerara, K.; /Paris U., VI-VII, LMCP; Tyliszczak, T.; /LBNL, ALS; Brown, G.E., Jr.; /Stanford U., Geo. Environ. Sci. /SLAC, SSRL

    2007-01-03

    Scanning Transmission X-ray Microscopy (STXM) and Transmission Electron Microscopy (TEM) were combined to characterize various samples of geomicrobiological interest down to the nanometer scale. An approach based on energy-filtered imaging was used to examine microbe-mineral interactions and the resulting biominerals, as well as biosignatures in simplified laboratory samples. This approach was then applied to natural samples, including natural biofilms entombed in calcium carbonate precipitates and bioweathered silicates and facilitated location of bacterial cells and provided unique insights about their biogeochemical interactions with minerals at the 30-40 nm scale.

  1. Multiscale 3D characterization with dark-field x-ray microscopy

    DEFF Research Database (Denmark)

    Simons, Hugh; Jakobsen, Anders Clemen; Ahl, Sonja Rosenlund

    2016-01-01

    Dark-field x-ray microscopy is a new way to three-dimensionally map lattice strain and orientation in crystalline matter. It is analogous to dark-field electron microscopy in that an objective lens magnifies diffracting features of the sample; however, the use of high-energy synchrotron x...... of the technique are presented-mapping the evolution of subgrains during the processing of plastically deformed aluminum, mapping domains and strain fields in ferroelectric crystals, and the three-dimensional mapping of strain fields around individual dislocations. This ability to directly characterize complex...

  2. Element-specific hysteresis loop measurements on Individual 35 nm islands with scanning transmission X-ray microscopy.

    Science.gov (United States)

    Luo, Feng; Eimüller, Thomas; Amaladass, Edward; Lee, Ming Sang; Heyderman, Laura J; Solak, Harun H; Tyliszczak, Tolek

    2012-03-01

    Using scanning transmission X-ray microscopy combined with X-ray magnetic circular dichroism, element-specific hysteresis loops with a 25 nm X-ray probe are obtained on 35 nm Fe/Gd multilayer nanoislands fabricated by extreme ultra-violet interference lithography. Local hysteresis loops measured for the individual islands and the antidot film between the islands display similar behavior resulting from the lateral confinement. Line scan measurements confirm ferrimagnetic coupling between Fe and Gd in the patterned region. The ability to measure magnetization reversal with X-rays at high spatial resolution will provide an important tool for future characterization of sub-50 nm nanostructures.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-11-24

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

  4. The architecture of amyloid-like peptide fibrils revealed by X-ray scattering, diffraction and electron microscopy

    DEFF Research Database (Denmark)

    Langkilde, Annette Eva; Morris, Kyle L; Serpell, Louise C;

    2015-01-01

    of the GNNQQNY peptide fragment of a yeast prion protein. Data from small-angle X-ray solution scattering, fibre diffraction and electron microscopy are combined with existing high-resolution X-ray crystallographic structures to investigate the fibrillation process and the hierarchical fibril structure...

  5. Scanning Transmission X-Ray, Laser Scanning, and Transmission Electron Microscopy Mapping of the Exopolymeric Matrix of Microbial Biofilms

    OpenAIRE

    Lawrence, J. R.; Swerhone, G. D. W.; Leppard, G. G.; T. Araki; Zhang, X.; West, M. M.; A. P. Hitchcock

    2003-01-01

    Confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and soft X-ray scanning transmission X-ray microscopy (STXM) were used to map the distribution of macromolecular subcomponents (e.g., polysaccharides, proteins, lipids, and nucleic acids) of biofilm cells and matrix. The biofilms were developed from river water supplemented with methanol, and although they comprised a complex microbial community, the biofilms were dominated by heterotrophic bacteria. TEM provid...

  6. Expansive reactions in concrete observed by soft x-ray transmission microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kurtis, K.E.; Monteiro, P.J.M. [Univ. of California, Berkeley, CA (United States). Dept. of Civil and Environmental Engineering; Brown, J.T.; Meyer-Ilse, W. [Lawrence Berkeley National Lab., CA (United States). Center for X-ray Optics

    1998-12-31

    Alkali-silica reaction, sulfate attack, and reinforcing steel corrosion can compromise the long-term durability of concrete structures. The anticipated economic impact of an extensive infrastructure repair scheme has produced a renewed interest in the development of advanced characterization methods to assess the degree of deterioration in the concrete experiencing these deleterious reactions. The products of the alkali silica reaction, sulfate attack, and corrosion as well as the cement hydration products are extremely sensitive to humidity. Consequently, characterization techniques that require high vacuum or drying, as many existing techniques do, are not particularly appropriate for the study of these reactions in concrete as artifacts are introduced. A high resolution instrument which allows the examination of these reactions and their products without drying and at normal pressures will promote understanding of the reactions and provide further insight into means of mitigating the damage they cause. Only soft x-ray transmission microscopy provides the required high spatial resolution to observe the reaction process in situ. The alkali-silica reaction can be observed over time, in a wet condition, and at normal pressures, features unavailable with most other high resolution techniques. Soft x-rays also reveal information on the internal structure of the sample. This paper reviews published and ongoing applications of soft x-ray transmission microscopy for the study of expansive reactions that occur in concrete.

  7. Soft X-ray Tomography and Cryogenic Light Microscopy: The Cool Combination in Cellular Imaging

    Science.gov (United States)

    McDermott, Gerry; Le Gros, Mark A.; Knoechel, Christian G.; Uchida, Maho; Larabell, Carolyn A.

    2012-01-01

    Soft x-ray tomography (SXT) is ideally suited to imaging sub-cellular architecture and organization, particularly in eukaryotic cells. SXT is similar in concept to the well-established medical diagnostic technique computed axial tomography (CAT), except SXT is capable of imaging with a spatial resolution of 50 nm, or better. In soft x-ray tomography (SXT) cells are imaged using photons from a region of the spectrum known as the ‘water window’. This results in quantitative, high-contrast images of intact, fully hydrated cells without the need to use contrast-enhancing agents. Cells are therefore visualized very close to their native, fully functional state. The utility of SXT has recently been enhanced by the development of high numerical aperture cryogenic light microscopy for correlated imaging. Taking this multi-modal approach now allows labeled molecules to be localized in the context of a high-resolution 3-dimensional tomographic reconstruction of the cell. PMID:19818625

  8. An environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Stephen T.; Nigge, P.; Prakash, Shruti; Laskin, Alexander; Wang, Bingbing; Tyliszczak, Tolek; Leone, Stephen R.; Gilles, Mary K.

    2013-08-01

    We have designed, fabricated, and tested a compact gas-phase reactor for performing in situ soft x-ray scanning transmission x-ray microscopy (STXM) measurements. The reactor accommodates many gas atmospheres, including reactive or corrosive gasses, but was designed specically to address the needs of measurements under water vapor. An on-board sensor measures the relative humidity and temperature inside the reactor, minimizing uncertainties associated with measuring these quantities outside the instrument. The reactor mounts directly to the existing sample holder used in the majority of STXM instruments around the world and installs with minimal instrument reconguration. Using the reactor contributes over 85% less additional absorption compared to lling the STXM chamber with process gas, and results in much more stable imaging conditions. The reactor is in use at the STXM instruments at beamlines 11.0.2 and 5.3.2.2 at the Advanced Light Source.

  9. Electron microscopy and microanalysis of steel weld joints after long time exposures at high temperatures

    Science.gov (United States)

    Jandová, D.; Kasl, J.; Rek, A.

    2010-02-01

    The structural changes of three trial weld joints of creep resistant modified 9Cr-1Mo steels and low alloyed chromium steel after post-weld heat treatment and long-term creep tests were investigated. Smooth cross-weld specimens ruptured in different zones of the weld joints as a result of different structural changes taking place during creep exposures. The microstructure of the weld joint is heterogeneous and consequently microstructural development can be different in the weld metal, the heat affected zone, and the base material. Precipitation reactions, nucleation and growth of some particles and dissolution of others, affect the strengthening of the matrix, recovery at high temperatures, and the resulting creep resistance. Therefore, a detailed study of secondary phase's development in individual zones of weld joints can elucidate mechanism of cracks propagation in specific regions and the causes of creep failure. Type I and II fractures in the weld metal and Type IV fractures in the fine prior austenite grain heat affected zones occurred after creep tests at temperatures ranging from 525 to 625 °C and under stresses from 40 to 240 MPa. An extended metallographic study of the weld joints was carried out using scanning and transmission electron microscopy, energy-dispersive and wave-dispersive X-ray microanalysis. Carbon extraction replicas and thin foils were prepared from individual weld joint regions and quantitative evaluation of dislocation substructure and particles of secondary phases has been performed.

  10. The Grizzly Lake complex (Yellowstone Volcano, USA): Mixing between basalt and rhyolite unraveled by microanalysis and X-ray microtomography

    Science.gov (United States)

    Morgavi, Daniele; Arzilli, Fabio; Pritchard, Chad; Perugini, Diego; Mancini, Lucia; Larson, Peter; Dingwell, Donald B.

    2016-09-01

    Magma mixing is a widespread petrogenetic process. It has long been suspected to operate in concert with fractional crystallization and assimilation to produce chemical and temperature gradients in magmas. In particular, the injection of mafic magmas into felsic magma chambers is widely regarded as a key driver in the sudden triggering of what often become highly explosive volcanic eruptions. Understanding the mechanistic event chain leading to such hazardous events is a scientific goal of high priority. Here we investigate a mingling event via the evidence preserved in mingled lavas using a combination of X-ray computed microtomographic and electron microprobe analyses, to unravel the complex textures and attendant chemical heterogeneities of the mixed basaltic and rhyolitic eruption of Grizzly Lake in the Norris-Mammoth corridor of the Yellowstone Plateau volcanic field (YVF). We observe evidence that both magmatic viscous inter-fingering of magmas and disequilibrium crystallization/dissolution processes occur. Furthermore, these processes constrain the timescale of interaction between the two magmatic components prior to their eruption. X-ray microtomography images show variegated textural features, involving vesicle and crystal distributions, filament morphology, the distribution of enclaves, and further textural features otherwise obscured in conventional 2D observations and analyses. Although our central effort was applied to the determination of mixing end members, analysis of the hybrid portion has led to the discovery that mixing in the Grizzly Lake system was also characterized by the disintegration and dissolution of mafic crystals in the rhyolitic magma. The presence of mineral phases in both end member, for example, forsteritic olivine, sanidine, and quartz and their transport throughout the magmatic mass, by a combination of both mixing dynamics and flow imposed by ascent of the magmatic mass and its eruption, might have acted as a "geometric

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

    Energy Technology Data Exchange (ETDEWEB)

    Puzic, Aleksandar

    2007-10-23

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

  12. Transmission x-ray microscopy at Diamond-Manchester I13 Imaging Branchline

    Science.gov (United States)

    Vila-Comamala, Joan; Bosgra, Jeroen; Eastwood, David S.; Wagner, Ulrich; Bodey, Andrew J.; Garcia-Fernandez, Miryam; David, Christian; Rau, Christoph

    2016-01-01

    Full-field Transmission X-ray Microscopy (TXM) has been shown to be a powerful method for obtaining quantitative internal structural and chemical information from materials at the nanoscale. The installation of a Full-field TXM station will extend the current microtomographic capabilities of the Diamond-Manchester I13 Imaging Branchline at Diamond Light Source (UK) into the sub-100 nm spatial resolution range using photon energies from 8 to 14 keV. The dedicated Full-field TXM station will be built in-house with contributions of Diamond Light Source support divisions and via collaboration with the X-ray Optics Group of Paul Scherrer Institut (Switzerland) which will develop state-of-the-art diffractive X-ray optical elements. Preliminary results of the I13 Full-field TXM station are shown. The Full-field TXM will become an important Diamond Light Source direct imaging asset for material science, energy science and biology at the nanoscale.

  13. Transmission x-ray microscopy at Diamond-Manchester I13 Imaging Branchline

    Energy Technology Data Exchange (ETDEWEB)

    Vila-Comamala, Joan, E-mail: joan.vila.comamala@gmail.com; Wagner, Ulrich; Bodey, Andrew J.; Garcia-Fernandez, Miryam; Rau, Christoph [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom); Bosgra, Jeroen; David, Christian [Paul Scherrer Institut, 5232 PSI-Villigen (Switzerland); Eastwood, David S. [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, Manchester M13 9PL, UK and Research Complex at Harwell, Harwell Campus, Didcot OX11 0FA (United Kingdom)

    2016-01-28

    Full-field Transmission X-ray Microscopy (TXM) has been shown to be a powerful method for obtaining quantitative internal structural and chemical information from materials at the nanoscale. The installation of a Full-field TXM station will extend the current microtomographic capabilities of the Diamond-Manchester I13 Imaging Branchline at Diamond Light Source (UK) into the sub-100 nm spatial resolution range using photon energies from 8 to 14 keV. The dedicated Full-field TXM station will be built in-house with contributions of Diamond Light Source support divisions and via collaboration with the X-ray Optics Group of Paul Scherrer Institut (Switzerland) which will develop state-of-the-art diffractive X-ray optical elements. Preliminary results of the I13 Full-field TXM station are shown. The Full-field TXM will become an important Diamond Light Source direct imaging asset for material science, energy science and biology at the nanoscale.

  14. An environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor.

    Science.gov (United States)

    Kelly, Stephen T; Nigge, Pascal; Prakash, Shruti; Laskin, Alexander; Wang, Bingbing; Tyliszczak, Tolek; Leone, Stephen R; Gilles, Mary K

    2013-07-01

    We have designed, fabricated, and tested a compact gas-phase reactor for performing in situ soft x-ray scanning transmission x-ray microscopy (STXM) measurements. The reactor mounts directly to the existing sample holder used in the majority of STXM instruments around the world and installs with minimal instrument reconfiguration. The reactor accommodates many gas atmospheres, but was designed specifically to address the needs of measurements under water vapor. An on-board sensor measures the relative humidity and temperature inside the reactor, minimizing uncertainties associated with measuring these quantities outside the instrument. The reactor reduces x-ray absorption from the process gas by over 85% compared to analogous experiments with the entire STXM instrument filled with process gas. Reduced absorption by the process gas allows data collection at full instrumental resolution, minimizes radiation dose to the sample, and results in much more stable imaging conditions. The reactor is in use at the STXM instruments at beamlines 11.0.2 and 5.3.2.2 at the Advanced Light Source.

  15. An environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Stephen T.; Nigge, Pascal; Prakash, Shruti; Gilles, Mary K. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Laskin, Alexander; Wang, Bingbing [William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Tyliszczak, Tolek [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Leone, Stephen R. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Chemistry and Department of Physics, University of California, Berkeley, California 94720 (United States)

    2013-07-15

    We have designed, fabricated, and tested a compact gas-phase reactor for performing in situ soft x-ray scanning transmission x-ray microscopy (STXM) measurements. The reactor mounts directly to the existing sample holder used in the majority of STXM instruments around the world and installs with minimal instrument reconfiguration. The reactor accommodates many gas atmospheres, but was designed specifically to address the needs of measurements under water vapor. An on-board sensor measures the relative humidity and temperature inside the reactor, minimizing uncertainties associated with measuring these quantities outside the instrument. The reactor reduces x-ray absorption from the process gas by over 85% compared to analogous experiments with the entire STXM instrument filled with process gas. Reduced absorption by the process gas allows data collection at full instrumental resolution, minimizes radiation dose to the sample, and results in much more stable imaging conditions. The reactor is in use at the STXM instruments at beamlines 11.0.2 and 5.3.2.2 at the Advanced Light Source.

  16. An environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor

    Science.gov (United States)

    Kelly, Stephen T.; Nigge, Pascal; Prakash, Shruti; Laskin, Alexander; Wang, Bingbing; Tyliszczak, Tolek; Leone, Stephen R.; Gilles, Mary K.

    2013-07-01

    We have designed, fabricated, and tested a compact gas-phase reactor for performing in situ soft x-ray scanning transmission x-ray microscopy (STXM) measurements. The reactor mounts directly to the existing sample holder used in the majority of STXM instruments around the world and installs with minimal instrument reconfiguration. The reactor accommodates many gas atmospheres, but was designed specifically to address the needs of measurements under water vapor. An on-board sensor measures the relative humidity and temperature inside the reactor, minimizing uncertainties associated with measuring these quantities outside the instrument. The reactor reduces x-ray absorption from the process gas by over 85% compared to analogous experiments with the entire STXM instrument filled with process gas. Reduced absorption by the process gas allows data collection at full instrumental resolution, minimizes radiation dose to the sample, and results in much more stable imaging conditions. The reactor is in use at the STXM instruments at beamlines 11.0.2 and 5.3.2.2 at the Advanced Light Source.

  17. Nondestructive characterization of municipal-solid-waste-contaminated surface soil by energy-dispersive X-ray fluorescence and low-Z (atomic number) particle electron probe X-ray microanalysis.

    Science.gov (United States)

    Gupta, Dhrubajyoti; Ghosh, Rita; Mitra, Ajoy K; Roy, Subinit; Sarkar, Manoranjan; Chowdhury, Subhajit; Bhowmik, Asit; Mukhopadhyay, Ujjal; Maskey, Shila; Ro, Chul-Un

    2011-11-01

    The long-term environmental impact of municipal solid waste (MSW) landfilling is still under investigation due to the lack of detailed characterization studies. A MSW landfill site, popularly known as Dhapa, in the eastern fringe of the metropolis of Kolkata, India, is the subject of present study. A vast area of Dhapa, adjoining the current core MSW dump site and evolving from the raw MSW dumping in the past, is presently used for the cultivation of vegetables. The inorganic chemical characteristics of the MSW-contaminated Dhapa surface soil (covering a 2-km stretch of the area) along with a natural composite (geogenic) soil sample (from a small countryside farm), for comparison, were investigated using two complementary nondestructive analytical techniques, energy-dispersive X-ray fluorescence (EDXRF) for bulk analysis and low-Z (atomic number) particle electron probe X-ray microanalysis (low-Z particle EPMA) for single-particle analysis. The bulk concentrations of K, Rb, and Zr remain almost unchanged in all the soil samples. The Dhapa soil is found to be polluted with heavy metals such as Cu, Zn, and Pb (highly elevated) and Ti, Cr, Mn, Fe, Ni, and Sr (moderately elevated), compared to the natural countryside soil. These high bulk concentration levels of heavy metals were compared with the Ecological Soil Screening Levels for these elements (U.S. Environment Protection Agency) to assess the potential risk on the immediate biotic environment. Low-Z particle EPMA results showed that the aluminosilicate-containing particles were the most abundant, followed by SiO2, CaCO3-containing, and carbonaceous particles in the Dhapa samples, whereas in the countryside sample only aluminosilicate-containing and SiO2 particles were observed. The mineral particles encountered in the countryside sample are solely of geogenic origin, whereas those from the Dhapa samples seem to have evolved from a mixture of raw dumped MSW, urban dust, and other contributing factors such as wind

  18. Transmission electron microscopy and x-ray diffraction studies of the detonation soot of high explosives

    Science.gov (United States)

    Kashkarov, A. O.; Pruuel, E. R.; Ten, K. A.; Rubtsov, I. A.; Gerasimov, E. Yu; Zubkov, P. I.

    2016-11-01

    This paper presents the results of electron microscopy and x-ray diffraction studies of the recovered carbonaceous residue (soot) from the detonation of some high explosives: TNT, a mixture of TNT and RDX (50/50), benzotrifuroxane, and triaminotrinitrobenzene. The use of the same experimental setup allowed a qualitative and quantitative comparison of the detonation products formed under similar conditions. The results clearly show differences in the morphology of graphite-like and diamond inclusions and in the quantitative content of nanodiamonds for the explosives used in this study.

  19. Phase contrast soft x-ray microscopy using Zernike zone plates.

    Science.gov (United States)

    Sakdinawat, Anne; Liu, Yanwei

    2008-02-04

    Soft x-ray Zernike phase contrast microscopy was implemented using a "Zernike zone plate" (ZZP) without the use of a separate phase filter in the back focal plane. The ZZP is a single optic that integrates the appropriate +/-pi/2 radians phase shift through selective zone placement shifts in a Fresnel zone plate. Imaging using a regular zone plate, positive ZZP, and negative ZZP was performed at a wavelength of lambda = 2.163 nm. Contrast enhancement with the positive ZZP and contrast reversal with the negative ZZP were observed.

  20. Application of soft X-ray microscopy to environmental microbiology of hydrosphere

    Science.gov (United States)

    Takemoto, K.; Yoshimura, M.; Ohigashi, T.; Inagaki, Y.; Namba, H.; Kihara, H.

    2017-06-01

    Microstructures of unprocessed filamentous cyanobacterium, Pseudanabaena foetida sp., producing a musty smell were observed using soft X-ray microscopy. Carbon-enriched structures and granules as well as oxygen-enriched granules which have been already reported were observed. Except for early log growth phase, the oxygen-enriched granules were observed. However, the carbon-enriched structures were observed throughout log growth phase. The result suggests there is a relationship between the oxygen-enriched granules and 2-methylisoborneol (2-MIB) productivity, since the 2-MIB productivity of each cell is increased depending on the culture period in log growth phase.

  1. Correlative Light and Scanning X-Ray Scattering Microscopy of Healthy and Pathologic Human Bone Sections

    Science.gov (United States)

    Giannini, C.; Siliqi, D.; Bunk, O.; Beraudi, A.; Ladisa, M.; Altamura, D.; Stea, S.; Baruffaldi, F.

    2012-01-01

    Scanning small and wide angle X-ray scattering (scanning SWAXS) experiments were performed on healthy and pathologic human bone sections. Via crystallographic tools the data were transformed into quantitative images and as such compared with circularly polarized light (CPL) microscopy images. SWAXS and CPL images allowed extracting information of the mineral nanocrystalline phase embedded, with and without preferred orientation, in the collagen fibrils, mapping local changes at sub-osteon resolution. This favorable combination has been applied for the first time to biopsies of dwarfism syndrome and Paget's disease to shed light onto the cortical structure of natural bone in healthy and pathologic sections. PMID:22666538

  2. Magnetic soft x-ray microscopy of the domain wall depinning process in permalloy magnetic nanowires.

    Science.gov (United States)

    Im, Mi-Young; Bocklage, Lars; Meier, Guido; Fischer, Peter

    2012-01-18

    Full-field magnetic transmission x-ray microscopy at high spatial resolution down to 20 nm is used to directly observe field-driven domain wall motion in notch-patterned permalloy nanowires. The depinning process of a domain wall around a notch exhibits a stochastic nature in most nanowires. The stochasticity of the domain wall depinning sensitively depends on the geometry of the nanowire such as the wire thickness, the wire width, and the notch depth. We propose an optimized design of the nanowire for deterministic domain wall depinning field at a notch.

  3. Scanning transmission X-ray microscopy with Fresnel Zone Plate beyond the expected resolution

    CERN Document Server

    Keskinbora, Kahraman; Weigand, Markus; Nadzeyka, Achim; Peto, Llyod; Schneider, Gerd; Vila-Comamala, Joan; Schütz, Gisela

    2012-01-01

    In X-ray microscopy the highest spatial resolutions to date are achieved by employing diffraction based elements called Fresnel Zone Plates (FZPs) as focusing optics. They allow potential resolutions which are determined by the width of their outermost zone period {\\Lambda} according to the Rayleigh criterion . Here, we present a FZP with an outermost period {\\Lambda} of 200 nm which possess a particular design and has been fabricated by ion beam lithography (IBL). Unexpectedly, the measured resolution is strongly dependent on the photon energy and at 450 eV the FZP is able to resolve features of 31 nm. This is approximately twice as high as the expected Rayleigh resolution.

  4. Measurement of the composition of noble-metal particles in high-burnup CANDU fuel by wavelength dispersive X-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Hocking, W.H.; Szostak, F.J

    1999-09-01

    An investigation of the composition of the metallic inclusions in CANDU fuel, which contain Mo, Tc, Ru, Rh and Pd, has been conducted as a function of burnup by wavelength dispersive X-ray (WDX) microanalysis. Quantitative measurements were performed on micrometer sized particles embedded in thin sections of fuel using elemental standards and the ZAF method. Because the fission yields of the noble metals change with burnup, as a consequence of a shift from almost entirely {sup 235}U fission to mainly {sup 239}Pu fission, their inventories were calculated from the fuel power histories using the WIMS-Origin code for comparison with experiment. Contrary to expectations that the oxygen potential would be buffered by progressive Mo oxidation, little evidence was obtained for reduced incorporation of Mo in the noble-metal particles at high burnup. These surprising results are discussed with respect to the oxygen balance in irradiated CANDU fuels and the likely intrinsic and extrinsic sinks for excess oxygen. (author)

  5. Investigation of Optically Modified YBa2Cu3O7–x Films by Means of X-ray Microanalysis Technique

    Directory of Open Access Journals (Sweden)

    Artūras JUKNA

    2014-06-01

    Full Text Available This work reports on investigation of remnant oxygen content in optically-modified regions of 0.3-mm-thick YBa2Cu3O7–x films, patterned by a laser-writing technique in an inert ambient gas atmosphere at room temperature. A laser-treated region of weak superconductivity with dimensions depending on the size of a laser spot, laser power, and initial content of oxygen is characterized by a lower oxygen content, weaker critical magnetic field, and suppressed both the superconducting critical temperature and the critical current density, as compared to the laser untreated regions. Optically induced (cw-laser, 532-nm-wavelength heating strongly affects a non-uniform distribution of remnant oxygen content in the film, depending both on the optical power and beam’s scanning velocity. A level of oxygen depletion and the size of the oxygen-deficient region have been directly estimated from scanning-electron-microscope spectra with the X-ray microanalysis technique. The results of our measurements were compared with results extracted from electric measurements, assuming a correlation between the remnant oxygen content and the electric transport properties of oxygen-deficient YBa2Cu3O7–x films. DOI: http://dx.doi.org/10.5755/j01.ms.20.2.6323

  6. Attenuated total reflectance FT-IR imaging and quantitative energy dispersive-electron probe X-ray microanalysis techniques for single particle analysis of atmospheric aerosol particles.

    Science.gov (United States)

    Ryu, JiYeon; Ro, Chul-Un

    2009-08-15

    This work demonstrates the practical applicability of the combined use of attenuated total reflectance (ATR) FT-IR imaging and low-Z particle electron probe X-ray microanalysis (EPMA) techniques for the characterization of individual aerosol particles. These two single particle analytical techniques provide complementary information on the physicochemical characteristics of the same individual particles, that is, the low-Z particle EPMA for the information on the morphology and elemental concentration and the ATR-FT-IR imaging on the functional group, molecular species, and crystal structure. It was confirmed that the ATR-FT-IR imaging technique can provide sufficient FT-IR absorption signals to perform molecular speciation of individual particles of micrometer size when applied to artificially generated aerosol particles such as ascorbic acid and NaNO(3) aerosols. An exemplar indoor atmospheric aerosol sample was investigated to demonstrate the practical feasibility of the combined application of ATR-FT-IR imaging and low-Z particle EPMA techniques for the characterization of individual airborne particles.

  7. X-Ray Microanalysis Investigation of the Changes in Na, K, and Hemoglobin Concentration in Plasmodium falciparum-Infected Red Blood Cells

    Science.gov (United States)

    Mauritz, Jakob M.A.; Seear, Rachel; Esposito, Alessandro; Kaminski, Clemens F.; Skepper, Jeremy N.; Warley, Alice; Lew, Virgilio L.; Tiffert, Teresa

    2011-01-01

    Plasmodium falciparum is responsible for severe malaria. During the ∼48 h duration of its asexual reproduction cycle in human red blood cells, the parasite causes profound alterations in the homeostasis of the host red cell, with reversal of the normal Na and K gradients across the host cell membrane, and a drastic fall in hemoglobin content. A question critical to our understanding of how the host cell retains its integrity for the duration of the cycle had been previously addressed by modeling the homeostasis of infected cells. The model predicted a critical contribution of excess hemoglobin consumption to cell integrity (the colloidosmotic hypothesis). Here we tested this prediction with the use of electron-probe x-ray microanalysis to measure the stage-related changes in Na, K, and Fe contents in single infected red cells and in uninfected controls. The results document a decrease in Fe signal with increased Na/K ratio. Interpreted in terms of concentrations, the results point to a sustained fall in host cell hemoglobin concentration with parasite maturation, supporting a colloidosmotic role of excess hemoglobin digestion. The results also provide, for the first time to our knowledge, comprehensive maps of the elemental distributions of Na, K, and Fe in falciparum-infected red blood cells. PMID:21402025

  8. Investigation of synthesized Be-bearing silicate glass as laboratory reference sample at X-ray electron probe microanalysis of silicates

    Science.gov (United States)

    Belozerova, Olga Yu.; Mikhailov, Mikhail A.; Demina, Tamara V.

    2017-01-01

    The article discusses estimates of the stability and homogeneity in Be-Mg-Al-silicate glass produced by the authors and its applicability as a laboratory reference sample for X-ray electron probe microanalysis (EPMA) of Be-bearing silicate matters: crystals and quenching melt (glasses), silicates and oxides. The results were obtained using Superprobe-733 and Superprobe JXA-8200 (JEOL Ltd, Japan) devices. The sample homogeneity was studied on macro (10-100 μm) and micro (1-10 μm) levels and was evaluated by the scheme of dispersion analysis. The applicability of Be-bearing silicate glass as a reference sample for Mg, Al, Si determinations was tested on the international certified reference glasses and laboratory reference samples of minerals with a known composition. The obtained experimental metrological characteristics correspond to the "applied geochemistry" type of analysis (second category) and suggest that Be-bearing silicate glass is appropriate as a laboratory reference sample for EPMA of Be-bearing silicate matters, silicates and oxides. Using Be-Mg-Al-silicate glass as a reference sample we obtained satisfactory data on the composition of both some minerals including cordierite and beryllium cordierite, beryllium indialite, beryl and metastable phases (chrysoberyl, compounds with structure of β-quartz and petalite).

  9. Multispecies Biofilms Transform Selenium Oxyanions into Elemental Selenium Particles: Studies Using Combined Synchrotron X-ray Fluorescence Imaging and Scanning Transmission X-ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Soo In; George, Graham N.; Lawrence, John R.; Kaminskyj, Susan G. W.; Dynes, James J.; Lai, Barry; Pickering, Ingrid J.

    2016-10-04

    Selenium (Se) is an element of growing environmental concern, because low aqueous concentrations can lead to biomagnification through the aquatic food web. Biofilms, naturally occurring microbial consortia, play numerous important roles in the environment, especially in biogeochemical cycling of toxic elements in aquatic systems. The complexity of naturally forming multispecies biofilms presents challenges for characterization because conventional microscopic techniques require chemical and physical modifications of the sample. Here, multispecies biofilms biotransforming selenium oxyanions were characterized using X-ray fluorescence imaging (XFI) and scanning transmission X-ray microscopy (STXM). These complementary synchrotron techniques required minimal sample preparation and were applied correlatively to the same biofilm areas. Sub-micrometer XFI showed distributions of Se and endogenous metals, while Se K-edge X-ray absorption spectroscopy indicated the presence of elemental Se (Se0). Nanoscale carbon K-edge STXM revealed the distributions of microbial cells, extracellular polymeric substances (EPS), and lipids using the protein, saccharide, and lipid signatures, respectively, together with highly localized Se0 using the Se LIII edge. Transmission electron microscopy showed the electron-dense particle diameter to be 50–700 nm, suggesting Se0 nanoparticles. The intimate association of Se0 particles with protein and polysaccharide biofilm components has implications for the bioavailability of selenium in the environment.

  10. Composition analysis of a polymer electrolyte membrane fuel cell microporous layer using scanning transmission X-ray microscopy and near edge X-ray absorption fine structure analysis

    Science.gov (United States)

    George, Michael G.; Wang, Jian; Banerjee, Rupak; Bazylak, Aimy

    2016-03-01

    The novel application of scanning transmission X-ray microscopy (STXM) to the microporous layer (MPL) of a polymer electrolyte membrane fuel cell is investigated. A spatially resolved chemical component distribution map is obtained for the MPL of a commercially available SGL 25 BC sample. This is achieved with near edge X-ray absorption fine structure spectroscopic analysis. Prior to analysis the sample is embedded in non-reactive epoxy and ultra-microtomed to a thickness of 100 nm. Polytetrafluoroethylene (PTFE), carbon particle agglomerates, and supporting epoxy resin distributions are identified and reconstructed for a scanning area of 6 μm × 6 μm. It is observed that the spatial distribution of PTFE is strongly correlated to the carbon particle agglomerations. Additionally, agglomerate structures of PTFE are identified, possibly indicating the presence of a unique mesostructure in the MPL. STXM analysis is presented as a useful technique for the investigation of chemical species distributions in the MPL.

  11. Visualization of the Cassie-Wenzel transition with X-ray microscopy

    Science.gov (United States)

    Lim, Su Jin; Kim, Yeseul; Jeong, Suyeon; Pang, Changhyun; Weon, Byung Mook

    2016-11-01

    Water droplets on hydrophobic surfaces with micropillar usually exhibit two wetting states: (i) the Cassie state when air is trapped between water and micropillars and (ii) the Wenzel state when air is completely replaced by water. A transition from the Cassie to the Wenzel states is essential in designing stable hydrophobic surfaces. Directly visualizing the Cassie-Wenzel (C-W) transition is difficult with conventional microscopies because of no transparency from micropillars. Here we suggest a powerful technique based on high-resolution high-penetration X-ray microscopy for clearly visualizing the C-W transition. Thanks to the X-ray penetrating into the opaque micropillars, we were able to directly explore the intermediate state during the C-W transition. We study on the transition dynamics regarding how air replacement by water was gradually propagated with position and time. We believe that the replacement dynamics would be explained as a kind of phase transition kinetics. This research was supported by Global Ph.D Fellowship Program and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015H1A2A1034133) (NRF-2016R1D1A1B01007133).

  12. SEM and x-ray microanalysis of cellular differentiation in Sea Urchin Embryos: a frozen hydrated study

    Energy Technology Data Exchange (ETDEWEB)

    Klein, S.B.

    1985-12-01

    Quantitative studies of major chemical element distribution among individual differentiating cells were attempted using scanning electron microscopy. Frozen hydrated embryos of the sea urchin Strongelocentrotus purpuratus were examined at three stages: blastula, mesenchyme blastula, and early gastrula. The blastocoel matrix contained large beads of approximately 1 ..mu..m diameter. The cells of the archenteron lacked well defined cell boundaries. Characteristic levels of beam damage and charging provided structural information. The primary mesenchyme cells within the blastocoel were particularly susceptible to both effects. Damaging effects were noted in material stored in liquid nitrogen longer than three months. Ice crystal growth, shrinkage, elemental shift, density changes and charge accumulation may take place in these stored specimens. 151 refs., 50 figs., 3 tabs.

  13. PREFACE: 11th International Conference on X-ray Microscopy (XRM2012)

    Science.gov (United States)

    Xu, Hongjie; Wu, Ziyu; Tai, Renzhong

    2013-10-01

    The Eleventh International Conference on X-ray Microscopy (XRM2012) was held on 5-10 August 2012 at the Hope hotel in Shanghai. Historically, for the first time the XRM conference took place in China. The conference was jointly hosted by the Shanghai Synchrotron Radiation Facility (SSRF) and the National Synchrotron Radiation Laboratory (NSRL). The series of XRM conferences dates back to 1983 in Göttingen, Germany. Since the Zürich conference, XRM2008, it has been held every two years, showing its increasing popularity among the x-ray microscopy communities around the world. Research in the area of x-ray microscopy is advancing very fast with the development of synchrotron radiation techniques, especially the emergence of third generation light sources with low natural emittance which has significantly pushed forward the development of technologies and applications in this area. This has been fully demonstrated in presentations from this and previous XRM conferences. XRM2012 was attended by 295 people including 21 invited speakers, 53 contributing speakers, 55 students, and 13 industry exhibitors. Over 232 abstracts were submitted for oral or poster presentation and 56 original, peer-reviewed papers are published in these proceedings. The conference was sponsored by the Chinese Academy of Sciences (CAS) and the National Natural Science Foundation of China (11210301016/A0802), and three gold sponsors active in industrial and technological fields related to x-ray microscopy. An exhibition booth was offered free to Australia synchrotron, the host for XRM2014, to promote the next conference which will be held in Melbourne, Australia in 2014. An unforgettable memory for most conference participants might be the charming night cruise along Pujiang river which was part of the welcome reception on the first evening. The Werner Meyer-Ilse Award (WMIA) prize this year was awarded to Irene Zanette (TU-München) and Stephan Werner (HZB-Berlin), the former for her pioneering

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

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

  15. High resolution transmission soft X-ray microscopy of deterioration products developed in large concrete dams

    Science.gov (United States)

    Kurtis; Monteiro; Brown; Meyer-Ilse

    1999-12-01

    In concrete structures, the reaction of certain siliceous aggregates with the highly alkaline concrete pore solution produces an alkali-silicate gel that can absorb water and expand. This reaction can lead to expansion, cracking, increased permeability, and decreased strength of the concrete. Massive concrete structures, such as dams, are particularly susceptible to the damage caused by the alkali-silica reaction because of the availability of water and because massive gravity dams usually do not contain steel reinforcement to restrain the expansion. Both the cement hydration products and alkali-silica reaction products are extremely sensitive to humidity. Consequently, characterization techniques that require high vacuum or drying, as many existing techniques do, are not particularly appropriate for the study of the alkali-silica reaction because artefacts are introduced. Environmental scanning electron micrographs and scanning electron micrographs with energy dispersive X-ray analysis results demonstrate the effect of drying on the morphology and chemical composition of the alkali-silicate reaction gel. Thus, the impetus for this research was the need to observe and characterize the alkali-silica reaction and its gel product on a microscopic level in a wet environment (i.e. without introducing artefacts due to drying). Only soft X-ray transmission microscopy provides the required high spatial resolution needed to observe the reaction process in situ. The alkali-silica reaction can be observed over time, in a wet condition, and at normal pressures, features unavailable with most other high resolution techniques. Soft X-rays also reveal information on the internal structure of the sample. The purpose of this paper is to present research, obtained using transmission soft X-ray microscopy, on the effect of concrete pore solution cations, namely sodium and calcium, on the product formed as a result of alkali attack. Alkali-silicate reaction (ASR) gel was obtained from

  16. Objective for EUV microscopy, EUV lithography, and x-ray imaging

    Science.gov (United States)

    Bitter, Manfred; Hill, Kenneth W.; Efthimion, Philip

    2016-05-03

    Disclosed is an imaging apparatus for EUV spectroscopy, EUV microscopy, EUV lithography, and x-ray imaging. This new imaging apparatus could, in particular, make significant contributions to EUV lithography at wavelengths in the range from 10 to 15 nm, which is presently being developed for the manufacturing of the next-generation integrated circuits. The disclosure provides a novel adjustable imaging apparatus that allows for the production of stigmatic images in x-ray imaging, EUV imaging, and EUVL. The imaging apparatus of the present invention incorporates additional properties compared to previously described objectives. The use of a pair of spherical reflectors containing a concave and convex arrangement has been applied to a EUV imaging system to allow for the image and optics to all be placed on the same side of a vacuum chamber. Additionally, the two spherical reflector segments previously described have been replaced by two full spheres or, more precisely, two spherical annuli, so that the total photon throughput is largely increased. Finally, the range of permissible Bragg angles and possible magnifications of the objective has been largely increased.

  17. Biomedical and agricultural applications of energy dispersive X-ray spectroscopy in electron microscopy.

    Science.gov (United States)

    Wyroba, Elżbieta; Suski, Szymon; Miller, Karolina; Bartosiewicz, Rafał

    2015-09-01

    Energy dispersive X-ray spectroscopy (EDS) in electron microscopy has been widely used in many research areas since it provides precise information on the chemical composition of subcellular structures that may be correlated with their high resolution images. In EDS the characteristic X-rays typical of each element are analyzed and the new detectors - an example of which we describe - allow for setting precisely the area of measurements and acquiring signals as a point analysis, as a linescan or in the image format of the desired area. Mapping of the elements requires stringent methods of sample preparation to prevent redistribution/loss of the elements as well as elimination of the risk of overlapping spectra. Both qualitative and quantitative analyses may be performed at a low probe current suitable for thin biological samples. Descriptions of preparation techniques, drawbacks and precautions necessary to obtain reliable results are provided, including data on standards, effects of specimen roughness and quantification. Data on EPMA application in different fields of biomedical and agricultural studies are reviewed. In this review we refer to recent EDS/EPMA applications in medical diagnostics, studies on air pollution and agrochemicals as well as on plant models used to monitor the environment.

  18. Magnetic x-ray microscopy at low temperatures – Visualization of flux distributions in superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Claudia, E-mail: stahl@is.mpg.de; Ruoß, Stephen; Weigand, Markus; Bechtel, Michael; Schütz, Gisela [Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569 Stuttgart (Germany); Albrecht, Joachim [Research Institute for Innovative Surfaces, FINO, Aalen University, Beethovenstraße 1, 73430 Aalen (Germany)

    2016-01-28

    X-ray Magnetic Circular Dichroism (XMCD) microscopy at liquid nitrogen temperature has been performed on bilayers of high-T{sub c} superconducting YBCO (YBa{sub 2}Cu{sub 3}O{sub 7-δ}) and soft-magnetic Co{sub 40}Fe{sub 40}B{sub 20}. This should allow us to map the magnetic flux density distribution in the current-carrying state of the superconductor with high spatial resolution. For that purpose the UHV scanning X-ray microscope MAXYMUS has been upgraded by a MMR Micro Miniature Joule-Thompson cryostat capable of temperatures between 75 K and 580 K. Resulting XMCD images of the magnetic flux density in the superconductor with a field of view ranging from millimeters to micrometers are presented. The microscope’s unique combination of total electron yield (TEY) measurements together with low temperatures offers novel possibilities concerning the current transport in superconductors on small length scales.

  19. X-ray photoemission electron microscopy for the study of semiconductor materials

    Energy Technology Data Exchange (ETDEWEB)

    Anders, S.; Stammler, T.; Padmore, H.A. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Terminello, L.J.; Jankowski, A.F. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States); Stoehr, J. [IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120 (United States); Diaz, J. [Departamento de Fisic, Facultad de Ciencias, Universidad de Oviedo, Avda. Calvo Sotelo s/n, Oviedo, 33007 (Spain); Cossy-Favre, A. [EMPA, Duebendorf, Ueberlandstrasse 129, 8600 Duebendorf (Switzerland); Singh, S. [Center for X-ray Lithography, University of Wisconsin-Madison, Stoughton, Wisconsin 53589 (United States)

    1998-11-01

    Photoemission Electron Microscopy using X-rays (X-PEEM) is a novel combination of two established materials analysis techniques{emdash}PEEM using UV light, and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. This combination allows the study of elemental composition and bonding structure of the sample by NEXAFS spectroscopy with a high spatial resolution given by the microscope. A simple, two lens, 10 kV operation voltage PEEM has been used at the Stanford Synchrotron Radiation Laboratory and at the Advanced Light Source (ALS) in Berkeley to study various problems including materials of interest for the semiconductor industry. In the present paper we give a short overview over the method and the instrument which was used, and describe in detail a number of applications. These applications include the study of the different phases of titanium disilicide, various phases of boron nitride, and the analysis of small particles. A brief outlook is given on possible new fields of application of the PEEM technique, and the development of new PEEM instruments. {copyright} {ital 1998 American Institute of Physics.}

  20. X-ray photoemission electron microscopy for the study of semiconductor materials

    Energy Technology Data Exchange (ETDEWEB)

    Anders, S.; Stammler, T.; Padmore, H. [Lawrence Berkeley National Lab., CA (United States). Advanced Light Source Div.; Terminello, L.J.; Jankowski, A.F. [Lawrence Livermore National Lab., CA (United States); Stohr, J. [IBM Almaden Research Center, San Jose, CA (United States); Diaz, J. [Univ. de Oviedo (Spain). Dept. de Fisica; Cossy-Gantner, A. [EMPA, Duebendorf (Germany)

    1998-03-01

    Photoemission Electron Microscopy (PEEM) using X-rays is a novel combination of two established materials analysis techniques--PEEM using UV light, and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. This combination allows the study of elemental composition and bonding structure of the sample by NEXAFS spectroscopy with a high spatial resolution given by the microscope. A simple, two lens, 10 kV operation voltage PEEM has been used at the Stanford Synchrotron Radiation Laboratory and at the Advanced Light Source (ALS) in Berkeley to study various problems including materials of interest for the semiconductor industry. In the present paper the authors give a short overview over the method and the instrument which was used, and describe in detail a number of applications. These applications include the study of the different phases of titanium disilicide, various phases of boron nitride, and the analysis of small particles. A brief outlook is given on possible new fields of application of the PEEM technique, and the development of new PEEM instruments.

  1. X-ray microscopy for in situ characterization of 3D nanostructural evolution in the laboratory

    Science.gov (United States)

    Hornberger, Benjamin; Bale, Hrishikesh; Merkle, Arno; Feser, Michael; Harris, William; Etchin, Sergey; Leibowitz, Marty; Qiu, Wei; Tkachuk, Andrei; Gu, Allen; Bradley, Robert S.; Lu, Xuekun; Withers, Philip J.; Clarke, Amy; Henderson, Kevin; Cordes, Nikolaus; Patterson, Brian M.

    2015-09-01

    X-ray microscopy (XRM) has emerged as a powerful technique that reveals 3D images and quantitative information of interior structures. XRM executed both in the laboratory and at the synchrotron have demonstrated critical analysis and materials characterization on meso-, micro-, and nanoscales, with spatial resolution down to 50 nm in laboratory systems. The non-destructive nature of X-rays has made the technique widely appealing, with potential for "4D" characterization, delivering 3D micro- and nanostructural information on the same sample as a function of sequential processing or experimental conditions. Understanding volumetric and nanostructural changes, such as solid deformation, pore evolution, and crack propagation are fundamental to understanding how materials form, deform, and perform. We will present recent instrumentation developments in laboratory based XRM including a novel in situ nanomechanical testing stage. These developments bridge the gap between existing in situ stages for micro scale XRM, and SEM/TEM techniques that offer nanometer resolution but are limited to analysis of surfaces or extremely thin samples whose behavior is strongly influenced by surface effects. Several applications will be presented including 3D-characterization and in situ mechanical testing of polymers, metal alloys, composites and biomaterials. They span multiple length scales from the micro- to the nanoscale and different mechanical testing modes such as compression, indentation and tension.

  2. Ultrasensitive Scanning Transmission X-ray Microscopy: Pushing the Limits of Time Resolution and Magnetic Sensitivity

    Science.gov (United States)

    Ohldag, Hendrik

    Understanding magnetic properties at ultrafast timescales is crucial for the development of new magnetic devices. Samples of interest are often thin film magnetic multilayers with thicknesses in the range of a few atomic layers. This fact alone presents a sensitivity challenge in STXM microscopy, which is more suited toward studying thicker samples. In addition the relevant time scale is of the order of 10 ps, which is well below the typical x-ray pulse length of 50 - 100 ps. The SSRL STXM is equipped with a single photon counting electronics that effectively allows using a double lock-in detection at 476MHz (the x-ray pulse frequency) and 1.28MHz (the synchrotron revelation frequency) to provide the required sensitivity. In the first year of operation the excellent spatial resolution, temporal stability and sensitivity of the detection electronics of this microscope has enabled researchers to acquire time resolved images of standing as well as traveling spin waves in a spin torque oscillator in real space as well as detect the real time spin accumulation in non magnetic Copper once a spin polarized current is injected into this material. The total magnetic moment is comparable to that of a single nanocube of magnetic Fe buried under a micron of non-magnetic material.

  3. Ion distribution measured by electron probe X-ray microanalysis in apoplastic and symplastic pathways in root cells in sunflower plants grown in saline medium

    Indian Academy of Sciences (India)

    Reza Ebrahimi; S C Bhatla

    2012-09-01

    Little is known about how salinity affects ions distribution in root apoplast and symplast. Using x-ray microanalysis, ions distribution and the relative contribution of apoplastic and symplastic pathways for delivery of ions to root xylem were studied in sunflower plants exposed to moderate salinity (EC=6). Cortical cells provided a considerably extended Na+ and Cl− storage facility. Their contents are greater in cytoplasm (root symplast) as compared to those in intercellular spaces (root apoplast). Hence, in this level of salinity, salt damage in sunflower is not dehydration due to extracellular accumulation of sodium and chloride ions, as suggested in the Oertli hypothesis. On the other hand, reduction in calcium content due to salinity in intercellular space is less than reduction in the cytoplasm of cortical cells. It seems that sodium inhibits the radial movement of calcium in symplastic pathway more than in the apoplastic pathway. The cell wall seems to have an important role in providing calcium for the apoplastic pathway. Redistribution of calcium from the cell wall to intercellular space is because of its tendency towards xylem through the apoplastic pathway. This might be a strategy to enhance loading of calcium to xylem elements and to reduce calcium deficiency in young leaves under salinity. This phenomenon may be able to increase salt tolerance in sunflower plants. Supplemental calcium has been found to be effective in reducing radial transport of Na+ across the root cells and their loading into the xylem, but not sodium absorption. Supplemental calcium enhanced Ca2+ uptake and influx into roots and transport to stele.

  4. X-ray micro-analysis of the mineralization patterns in developing enamel in hamster tooth germs exposed to fluoride in vitro during the secretory phase of amelogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Lyaruu, D.M.; Blijleven, N.; Hoeben-Schornagel, K.; Bronckers, A.L.; Woeltgens, J.H.

    1989-09-01

    The developing enamel from three-day-old hamster first maxillary (M1) molar tooth germs exposed to fluoride (F-) in vitro was analyzed for its mineral content by means of the energy-dispersive x-ray microanalysis technique. The aim of this study was to obtain semi-quantitative data on the F(-)-induced hypermineralization patterns in the enamel and to confirm that the increase in electron density observed in micrographs of F(-)-treated enamel is indeed due to an increase in mineral content in the fluorotic enamel. The tooth germs were explanted during the early stages of secretory amelogenesis and initially cultured for 24 hr in the presence of 10 ppm F- in the culture medium. The germs were then cultured for another 24 hr without F-. In order to compare the ultrastructural results directly with the microprobe data, we used the same specimens for both investigations. The net calcium counts (measurement minus background counts) in the analyses were used as a measure of the mineral content in the enamel. The aprismatic pre-exposure enamel, deposited in vivo before the onset of culture, was the most hypermineralized region in the fluorotic enamel, i.e., it contained the highest amount of calcium measured. The degree of the F(-)-induced hypermineralization gradually decreased (but was not abolished) in the more mature regions of the enamel. The unmineralized enamel matrix secreted during the initial F- treatment in vitro mineralized during the subsequent culture without F-. The calcium content in this enamel layer was in the same order of magnitude as that recorded for the newly deposited enamel in control tooth germs cultured without F-.

  5. Cell viability evaluation of transdifferentiated endothelial-like cells by quantitative electron-probe X-ray microanalysis for tissue engineering.

    Science.gov (United States)

    Vico, Manuel; Rodríguez-Morata, Alejandro; Garzón, Ingrid; Campos, Fernando; Jaimes-Parra, Boris; Pérez-Köhler, Barbara; Buján, Julia; Alaminos, Miguel; Sánchez-Quevedo, M Carmen

    2015-11-01

    Development of an efficient vascular substitute by tissue engineering is strongly dependent on endothelial cell viability. The aim of this study was to evaluate cell viability of transdifferentiated endothelial-like cells (Tr-ELC) by using for the first time electron probe X-ray microanalysis (EPXMA), not only to accurately analyze cell viability by quantifying the intracellular ionic concentrations, but also to establish their possible use in vascular tissue engineering protocols. Human umbilical cord Wharton's jelly stem cells (HWJSC) and endothelial cells from the human umbilical vein (HUVEC) were isolated and cultured. Transdifferentiation from HWJSC to the endothelial phenotype was induced. EPXMA was carried out to analyze HUVEC, HWJSC and Tr-ELC cells by using a scanning electron microscope equipped with an EDAX DX-4 microanalytical system and a solid-state backscattered electron detector. To determine total ion content, the peak-to-local-background (P/B) ratio method was used with reference to standards composed of dextran containing known amounts of inorganic salts. Our results revealed a high K/Na ratio in Tr-ELC (9.41), in association with the maintenance of the intracellular levels of chlorine, phosphorous and magnesium and an increase of calcium (p=0.031) and sulfur (p=0.022) as compared to HWJSC. Calcium levels were similar for HUVEC and Tr-ELC. These results ensure that transdifferentiated cells are highly viable and resemble the phenotypic and microanalytical profile of endothelial cells. Tr-ELC induced from HWJSC may fulfill the requirements for use in tissue engineering protocols applied to the vascular system at the viability and microanalytical levels.

  6. Ion distribution measured by electron probe X-ray microanalysis in apoplastic and symplastic pathways in root cells in sunflower plants grown in saline medium.

    Science.gov (United States)

    Ebrahimi, Reza; Bhatla, S C

    2012-09-01

    Little is known about how salinity affects ions distribution in root apoplast and symplast. Using x-ray microanalysis, ions distribution and the relative contribution of apoplastic and symplastic pathways for delivery of ions to root xylem were studied in sunflower plants exposed to moderate salinity (EC=6). Cortical cells provided a considerably extended Na(+) and Cl(-) storage facility. Their contents are greater in cytoplasm (root symplast) as compared to those in intercellular spaces (root apoplast). Hence, in this level of salinity, salt damage in sunflower is not dehydration due to extracellular accumulation of sodium and chloride ions, as suggested in the Oertli hypothesis. On the other hand, reduction in calcium content due to salinity in intercellular space is less than reduction in the cytoplasm of cortical cells. It seems that sodium inhibits the radial movement of calcium in symplastic pathway more than in the apoplastic pathway. The cell wall seems to have an important role in providing calcium for the apoplastic pathway. Redistribution of calcium from the cell wall to intercellular space is because of its tendency towards xylem through the apoplastic pathway. This might be a strategy to enhance loading of calcium to xylem elements and to reduce calcium deficiency in young leaves under salinity. This phenomenon may be able to increase salt tolerance in sunflower plants. Supplemental calcium has been found to be effective in reducing radial transport of Na(+) across the root cells and their loading into the xylem, but not sodium absorption. Supplemental calcium enhanced Ca(2+) uptake and influx into roots and transport to stele.

  7. Fossilization in Geopark Araripe studied through X-ray diffraction, scanning microscopy and thermogravimetric analysis

    CERN Document Server

    Lima, Ricardo J C; Macedo, Zélia S; Sasaki, José M; Saraiva, Antônio A F

    2008-01-01

    The Geopark Araripe, located in Northeastern Brazil, is the first UNESCO Natural Park in the South hemisphere and a world-famous fossil deposit of the Early Cretaceous period (approximately 120 million years). Fossilized fish fauna in Geopark Araripe is found inside of sedimentary rocks in three-dimensional forms. In the present study sedimentary rocks and fossil fish Rhacolepis bucalis have been carefully analysed by means of X-ray powder diffraction, scanning electron microscopy and termogravimetric analysis. Mineralogical composition of the fossil fish was explained in terms of facts occurred at the initial stages of the opening of the South Atlantic and the oceanic hydrothermal phenomena (``black smoker'', ``white smoker'' and warm-water events). The occurrence of organic substance was, for the first time, evaluated in collapsed internal elements (intestinal and muscles) by termogravimetric analysis.

  8. Adenovirus Structure as Revealed by X-Ray Crystallography, Electron Microscopy, and Difference Imaging

    Science.gov (United States)

    Stewart, Phoebe L.; Burnett, Roger M.

    1993-03-01

    The three-dimensional structure of human type 2 adenovirus was studied by combining X-ray crystallography and electron microscopy in a novel way. The 2.9 Å crystal structure of the major capsid protein, hexon, was positioned into a three-dimensional image reconstruction of the intact virus that was derived from cryo-electron micrographs. A three-dimensional difference map was generated by subtracting 240 copies of the crystallographic hexon from the density of the intact virus. This map revealed several minor structural proteins acting as “cement” to stabilize the assembly. The current state of structural knowledge concerning the location of the polypeptide components and the viral DNA is presented.

  9. Investigations of Silk Fibers Using X-Ray Scattering and Atomic Force Microscopy

    Science.gov (United States)

    Miller, Lance D.; Putthanarat, Sirina; Eby, Ronald K.; Adams, W. W.; Liu, G. F.

    1998-03-01

    Silk fibers from the cocoon of Bombyx mori and the dragline of Nephila clavipes have been investigated by small angle x-ray scattering (SAXS) and atomic force microscopy (AFM). The large scale morphology of these silks have minimum scattering dimensions, and correlation length on the order of 150-300 nm. Several types of AFM measurements on peeled and abraided silk samples have revealed dimensions in agreement with SAXS results. Further agreemeent has been found through the incorporation of discrete Fourier transform theory on AFM topographic information as compared to SAXS patterns. This incorporation allows the materials scientist a way of visualizing the relationship between a material and its resulting scattering function. All of these studies yield a more complete view of the silk morphology and give a new method of model building from scattering experiments.

  10. Subsurface Grain Morphology Reconstruction by Differential Aperture X-ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Eisenlohr, Philip; Shanthraj, Pratheek; Vande Kieft, Brendan R.; Bieler, Thomas R.; Liu, Wenjun; Xu, Ruqing

    2017-04-27

    A multistep, non-destructive grain morphology reconstruction methodology that is applicable to near-surface volumes is developed and tested on synthetic grain structures. This approach probes the subsurface crystal orientation using differential aperture X-ray microscopy (DAXM) on a sparse grid across the microstructure volume of interest. Resulting orientation data is clustered according to proximity in physical and orientation space and used as seed points for an initial Voronoi tessellation to (crudely) approximate the grain morphology. Curvature-driven grain boundary relaxation, simulated by means of the Voronoi Implicit Interface Method (VIIM), progressively improves the reconstruction accuracy. The similarity between bulk and readily accessible surface reconstruction error provides an objective termination criterion for boundary relaxation.

  11. Lateral spin transfer torque induced magnetic switching at room temperature demonstrated by x-ray microscopy.

    Science.gov (United States)

    Buhl, M; Erbe, A; Grebing, J; Wintz, S; Raabe, J; Fassbender, J

    2013-01-01

    Changing and detecting the orientation of nanomagnetic structures, which can be used for durable information storage, needs to be developed towards true nanoscale dimensions for keeping up the miniaturization speed of modern nanoelectronic components. Therefore, new concepts for controlling the state of nanomagnets are currently in the focus of research in the field of nanoelectronics. Here, we demonstrate reproducible switching of a purely metallic nanopillar placed on a lead that conducts a spin-polarized current at room temperature. Spin diffusion across the metal-metal (Cu to CoFe) interface between the pillar and the lead causes spin accumulation in the pillar, which may then be used to set the magnetic orientation of the pillar. In our experiments, the detection of the magnetic state of the nanopillar is performed by direct imaging via scanning transmission x-ray microscopy (STXM).

  12. Lateral spin transfer torque induced magnetic switching at room temperature demonstrated by x-ray microscopy

    Science.gov (United States)

    Buhl, M.; Erbe, A.; Grebing, J.; Wintz, S.; Raabe, J.; Fassbender, J.

    2013-01-01

    Changing and detecting the orientation of nanomagnetic structures, which can be used for durable information storage, needs to be developed towards true nanoscale dimensions for keeping up the miniaturization speed of modern nanoelectronic components. Therefore, new concepts for controlling the state of nanomagnets are currently in the focus of research in the field of nanoelectronics. Here, we demonstrate reproducible switching of a purely metallic nanopillar placed on a lead that conducts a spin-polarized current at room temperature. Spin diffusion across the metal-metal (Cu to CoFe) interface between the pillar and the lead causes spin accumulation in the pillar, which may then be used to set the magnetic orientation of the pillar. In our experiments, the detection of the magnetic state of the nanopillar is performed by direct imaging via scanning transmission x-ray microscopy (STXM). PMID:24126435

  13. Small angle x-ray scattering and electron microscopy of nanoparticles formed in an electrical arc

    Directory of Open Access Journals (Sweden)

    E. Carvou

    2013-03-01

    Full Text Available Small Angle X-ray Scattering has been used to characterize nanoparticles generated by electrical arcing between metallic (AgSnO2 electrodes. The particles are found to have diameters between 30 and 40 nm and display smooth surfaces suggesting that they are either in liquid form or have solidified from the liquid state. Particles collected around the electrodes were analyzed by Transmission Electron Microscopy and were seen to be much larger than those seen in the SAXS measurement, to be spherical in form and composed of silver metal with irregular tin oxide particles deposited on their surface. Mixed metal nanoparticles can have important practical applications and the use of mixed sintered electrodes may be a direct method for their production.

  14. Small angle x-ray scattering and electron microscopy of nanoparticles formed in an electrical arc

    Science.gov (United States)

    Carvou, E.; Garrec, J. L. Le; Pérez, J.; Praquin, J.; Djeddi, M.; Mitchell, J. B. A.

    2013-03-01

    Small Angle X-ray Scattering has been used to characterize nanoparticles generated by electrical arcing between metallic (AgSnO2) electrodes. The particles are found to have diameters between 30 and 40 nm and display smooth surfaces suggesting that they are either in liquid form or have solidified from the liquid state. Particles collected around the electrodes were analyzed by Transmission Electron Microscopy and were seen to be much larger than those seen in the SAXS measurement, to be spherical in form and composed of silver metal with irregular tin oxide particles deposited on their surface. Mixed metal nanoparticles can have important practical applications and the use of mixed sintered electrodes may be a direct method for their production.

  15. Comparison of SOFC Cathode Microstructure Quantified using X-ray Nanotomography and Focused Ion Beam - Scanning Electron Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, George J. [Univ. of Connecticut, Storrs, CT (United States); Harris, William H. [Univ. of Connecticut, Storrs, CT (United States); Lombardo, Jeffrey J. [Univ. of Connecticut, Storrs, CT (United States); Izzo, Jr., John R. [Univ. of Connecticut, Storrs, CT (United States); Chiu, W. K. S. [Univ. of Connecticut, Storrs, CT (United States); Tanasini, Pietro [Ecole Ploytechnique Federale de Lausanne (Switzerland); Cantoni, Marco [Ecole Ploytechnique Federale de Lausanne (Switzerland); Van herle, Jan [Ecole Ploytechnique Federale de Lausanne (Switzerland); Comninellis, Christos [Ecole Ploytechnique Federale de Lausanne (Switzerland); Andrews, Joy C. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Liu, Yijin [SLAC National Accelerator Lab., Menlo Park, CA (United States); Pianetta, Piero [SLAC National Accelerator Lab., Menlo Park, CA (United States); Chu, Yong [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2011-03-24

    X-ray nanotomography and focused ion beam scanning electron microscopy (FIB-SEM) have been applied to investigate the complex 3D microstructure of solid oxide fuel cell (SOFC) electrodes at spatial resolutions of 45 nm and below. The application of near edge differential absorption for x-ray nanotomography and energy selected backscatter detection for FIB–SEM enable elemental mapping within the microstructure. Using these methods, non-destructive 3D x-ray imaging and FIB–SEM serial sectioning have been applied to compare three-dimensional elemental mapping of the LSM, YSZ, and pore phases in the SOFC cathode microstructure. The microstructural characterization of an SOFC cathode is reported based on these measurements. The results presented demonstrate the viability of x-ray nanotomography as a quantitative characterization technique and provide key insights into the SOFC cathode microstructure.

  16. Characterization of X-ray polycapillary optics by LiF crystal radiation detectors through confocal fluorescence microscopy

    Science.gov (United States)

    Bonfigli, Francesca; Hampai, Dariush; Dabagov, Sultan B.; Montereali, Rosa Maria

    2016-08-01

    Solid-state radiation imaging detectors based on photoluminescent colour centres in lithium fluoride (LiF) crystals have been successfully tested for both advanced 2D and 3D characterizations of X-ray polycapillary optics by a table-top laboratory system. Polycapillary optics can control X-ray beams propagation and allows obtaining quasi-parallel beam (half-lens) or focused beams (full-lens). The combination of a fine-focused micro X-ray tube and a polycapillary lens can provide the high intensity radiation fluxes that are necessary for high resolution X-ray imaging. In this paper we present novel results about advanced characterization of these complex optics by 2D as well as 3D confocal laser fluorescence microscopy of X-ray irradiated LiF crystal detectors. Two dimensional high spatial resolution images on a wide field of view of transmitted X-rays through a semi-lens and 3D direct inspection of the coloured volumes produced in LiF crystals by both focused and parallel X-ray beam transmitted by a full and a semi-lens, respectively, as well as their 3D reconstructions were obtained. The results show that the photoluminescent colour centres volume in LiF crystals combined with an optical sectioning reading system provide information about tomography of transmitted X-ray beams by policapillary optics in a single exposure process. For the first time, the use of LiF crystal plates as versatile radiation imaging luminescent detectors have been used to characterize the operation of polycapillary optics as X-ray lens, in focusing and parallel mode.

  17. High-resolution diffraction microscopy using the plane-wave field of a nearly diffraction limited focused x-ray beam

    OpenAIRE

    Takahashi, Yukio; Nishino, Yoshinori; Tsutsumi, Ryosuke; Kubo, Hideto; Furukawa, Hayato; Mimura, Hidekazu; MATSUYAMA, Satoshi; Zettsu, Nobuyuki; Matsubara, Eiichiro; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2009-01-01

    X-ray waves in the center of the beam waist of nearly diffraction limited focused x-ray beams can be considered to have amplitude and phase that are both almost uniform, i.e., they are x-ray plane waves. Here we report the results of an experimental demonstration of high-resolution diffraction microscopy using the x-ray plane wave of the synchrotron x-ray beam focused using Kirkpatrik-Baez mirrors. A silver nanocube with an edge length of ∼100 nm is illuminated with the x-ray beam focused to ...

  18. Characterization of polymer monoliths containing embedded nanoparticles by scanning transmission X-ray microscopy (STXM).

    Science.gov (United States)

    Arrua, R Dario; Hitchcock, Adam P; Hon, Wei Boon; West, Marcia; Hilder, Emily F

    2014-03-18

    The structural and chemical homogeneity of monolithic columns is a key parameter for high efficiency stationary phases in liquid chromatography. Improved characterization techniques are needed to better understand the polymer morphology and its optimization. Here the analysis of polymer monoliths by scanning transmission X-ray microscopy (STXM) is presented for the first time. Poly(butyl methacrylate-co-ethyleneglycoldimethacrylate) [poly(BuMA-co-EDMA)] monoliths containing encapsulated divinylbenzene (DVB) nanoparticles were characterized by STXM, which gives a comprehensive, quantitative chemical analysis of the monolith at a spatial resolution of 30 nm. The results are compared with other methods commonly used for the characterization of polymer monoliths [scanning electron microscopy (SEM), transmission electron microscopy (TEM), mercury porosimetry, and nitrogen adsorption]. The technique permitted chemical identification and mapping of the nanoparticles within the polymeric scaffold. Residual surfactant, which was used during the manufacture of the nanoparticles, was also detected. We show that STXM can give more in-depth chemical information for these types of materials and therefore lead to a better understanding of the link between polymer morphology and chromatographic performance.

  19. Qualitative detection of single submicron and nanoparticles in human skin by scanning transmission x-ray microscopy

    Science.gov (United States)

    Graf, Christina; Meinke, Martina; Gao, Qi; Hadam, Sabrina; Raabe, Jörg; Sterry, Wolfram; Blume-Peytavi, Ulrike; Lademann, Jürgen; Rühl, Eckart; Vogt, Annika

    2009-03-01

    First results on single particle detection in human skin samples by x-ray microscopy are reported. 94+/-6 and 161+/-13 nm gold core particles with silica shells and 298+/-11 nm silica particles coated with a gold shell on ultramicrotome sections of human skin were determined. The particles were applied on fresh intact skin samples, which were sectioned prior to imaging. After screening the sections by conventional microscopy techniques, defined areas of interest were qualitatively investigated by scanning transmission x-ray microscopy at the Swiss Light Source. In studies on the percutaneous penetration of 161+/-13 nm particles on human skin samples, x-ray microscopy yielded high-resolution images of single particles spreading on the superficial layer of the stratum corneum and on the epithelium in superficial parts of hair follicles. No deeper penetration was observed. The present work using x-ray microscopy provides the unique opportunity to study qualitative penetration processes and membrane-particle interactions on the level of single particles. This goes beyond present approaches using optical microscopy. Further improvement of this approach will allow one to study particles with different physicochemical properties and surface modifications, including responses of the exposed tissue.

  20. Recent investigations of silk fibers utilizing x-ray scattering and atomic force microscopy

    Science.gov (United States)

    Miller, Lance D.

    1998-12-01

    Silks from the mulberry silkworm, Bombyx mori, and the golden-orb spider, Nephila clavipes, are materials that possess respectable properties. Even pitted against the high performance fibers of Kevlar, polyethylene, and carbon, the advantages of some of nature's fibers are clear. The tensile strength of the golden-orb spider dragline is of the same order of magnitude as many synthetic fibers, yet the dragline's compressive strength as a percentage of its tensile strength is greater. The spider's ampullate glands, responsible for the manufacture of the dragline, also excel. The spider spins its fiber from a liquid crystalline solution that is water based versus the solutions at high temperatures containing volatile solvents that are required for current synthetic fibers. Understanding the morphology of silks will provide the basis for improved manufacturing and better performing synthetic fibers. The studies presented here have centered on the use of small-angle x-ray scattering, SAXS, to describe the large-scale morphology of silk fibers. We have determined minimum scattering dimensions on the order of 150-300 nm. A detailed analysis of the Porod scattering region has revealed correlation lengths of the same magnitude. Both of these dimensions are similar to with direct atomic force microscopy, AFM, measurements of nanofibers found in samples of abraded or peeled silk. The incorporation of discrete Fourier transform theory and AFM topographic information has yielded results in general agreement with measured SAXS patterns. This incorporation allows the materials scientist a way of visualizing the relationship between a material and its resulting scattering function. We have also found that x-ray scattering gives insight to new periodic distances of the morphology of golden-orb dragline. All of these studies yield a more complete view of the silk morphology and give a new method of model building from scattering experiments.

  1. Development of in-line furnace for in-situ nanoscale resolution x-ray microscopy

    Science.gov (United States)

    Eng, Christopher; Chen-Wiegart, Yu-Chen K.; Wang, Jun

    2013-09-01

    Full field transmission x-ray microscopy (TXM) is a newly developed x-ray imaging technique to provide quantitative and non-destructive 3D characterization of the complex microstructure of materials at nanometer resolution. A key missing component is an in situ apparatus enabling the imaging of the complex structural evolution of the materials and to correlate the structural change with a material's functionality under real operating conditions. This work describes the design of an environmental cell which satisfies the requirements for in situ TXM studies. The limited space within the TXM presents a spatial constraint which prohibits the use of conventional heaters, as well as requiring consideration in designing for safe and controlled operation of the system and alignment of the cell with the beam. A gravity drip-fed water cooling jacket was installed in place around the heating module to maintain critical components of the microscope at safe operating temperatures. A motion control system consisting of pulse width modulated DC motor driven XYZ translation stages was developed to facilitate fine alignment of the cell. Temperature of the sample can be controlled remotely and accurately through a controller to temperatures as high as 1200 K. Heating zone measurement was carried out and shows a 500 x 500 x 500 μm3 homogeneous zone volume for sample area, which is a critical parameter to ensure accurate observation of structural evolution at nanometer scale with a sample in size of tens of microns. Application on Ni particles for in situ oxidation experiment and dehydrogenation of aluminum hydride is also discussed.

  2. Spatial Gradients in Particle Reinforced Polymers Characterized by X-Ray Attenuation and Laser Confocal Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    LAGASSE,ROBERT R.; THOMPSON,KYLE R.

    2000-06-12

    The goal of this work is to develop techniques for measuring gradients in particle concentration within filled polymers, such as encapsulant. A high concentration of filler particles is added to such materials to tailor physical properties such as thermal expansion coefficient. Sedimentation and flow-induced migration of particles can produce concentration gradients that are most severe near material boundaries. Therefore, techniques for measuring local particle concentration should be accurate near boundaries. Particle gradients in an alumina-filled epoxy resin are measured with a spatial resolution of 0.2 mm using an x-ray beam attenuation technique, but an artifact related to the finite diameter of the beam reduces accuracy near the specimen's edge. Local particle concentration near an edge can be measured more reliably using microscopy coupled with image analysis. This is illustrated by measuring concentration profiles of glass particles having 40 {micro}m median diameter using images acquired by a confocal laser fluorescence microscope. The mean of the measured profiles of volume fraction agrees to better than 3% with the expected value, and the shape of the profiles agrees qualitatively with simple theory for sedimentation of monodisperse particles. Extending this microscopy technique to smaller, micron-scale filler particles used in encapsulant for microelectronic devices is illustrated by measuring the local concentration of an epoxy resin containing 0.41 volume fraction of silica.

  3. Characterisation by X-ray microanalysis of metal granules in the mucus trails of Littorina littorea (Gastropoda) along a putative pollution gradient.

    Science.gov (United States)

    Reboreda, R; Davies, Mark S

    2006-07-01

    Metal-containing granules in the mucus trails of the marine gastropod Littorina littorea from nine sites in north-east England were analysed for elemental composition by X-ray microanalysis and characterised relative to a putative gradient of pollution. Overall granule density varied significantly between sites, means of 6.5-17.0 per field of view (2688 microm2). Most granules found (64%) were poly-metal of a wide variety of compositions, but could be classified as Si+X, Mg+X, S+X, Na+X, P+Ca, P+Al, where X indicates any other combination of elements. Si+Al+X accounted for 61% of the poly-metal granules found and was considered to be contamination from the beach substratum. In single-metal granule form only Ca, Si, Fe, Ti, Al and Na were found. The most common single-metal granule at each site was of Ca, except at two sites, where the most common single-metal granule was of Si. The densities of these granule types varied between sites but differences were found to be significant only in the case of Si granules. Across all sites, single-metal granules of Si (mean = 2.49 microm +/- 1.44 SD, n = 141) and Ca (2.22 microm +/- 1.08 SD, n = 147) were significantly larger than granules of Fe (1.74 microm +/- 0.95 SD, n = 63) and Ti (1.24 microm +/- 0.52 SD, n = 18). The range of sizes was large: Ca (0.5-6 microm), Si (0.5-10 microm), Fe (0.3-4.1 microm), Ti (0.5-2.5 microm). Between the sites there were significant differences in the size of Fe and Si granules but not Ca or Ti granules. Despite these variations in granule type and size, there was no evidence of a relationship with pollution and consequently a detoxifying function of the mucus trail in metal polluted environments is not apparent.

  4. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    Science.gov (United States)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-01-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties. PMID:27087141

  5. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    Science.gov (United States)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-04-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties.

  6. Integrated circuit authentication using photon-limited x-ray microscopy.

    Science.gov (United States)

    Markman, Adam; Javidi, Bahram

    2016-07-15

    A counterfeit integrated circuit (IC) may contain subtle changes to its circuit configuration. These changes may be observed when imaged using an x-ray; however, the energy from the x-ray can potentially damage the IC. We have investigated a technique to authenticate ICs under photon-limited x-ray imaging. We modeled an x-ray image with lower energy by generating a photon-limited image from a real x-ray image using a weighted photon-counting method. We performed feature extraction on the image using the speeded-up robust features (SURF) algorithm. We then authenticated the IC by comparing the SURF features to a database of SURF features from authentic and counterfeit ICs. Our experimental results with real and counterfeit ICs using an x-ray microscope demonstrate that we can correctly authenticate an IC image captured using orders of magnitude lower energy x-rays. To the best of our knowledge, this Letter is the first one on using a photon-counting x-ray imaging model and relevant algorithms to authenticate ICs to prevent potential damage.

  7. Experimental Study on Soft X-ray Contact Microscopy for Biological Specimens

    Institute of Scientific and Technical Information of China (English)

    XIE Honglan; GAO Hongyi; JIANG Shiping; CHEN Jianwen; LU Peixiang; XU Zhizhan

    2002-01-01

    Using Hefei Synchrotron radiation as X-ray source and photoresist PMMA as recording medium, soft X-ray contact microscopic imaging experiment on hydrated leaf epidermal cells of a kind of dicotyledon is performed and its latent image is read out by a light microscope. Several main factors degrading the resolution of the image are discussed in detail.

  8. Correlating metal poisoning with zeolite deactivation in an individual catalyst particle by chemical and phase sensitive X-ray microscopy

    NARCIS (Netherlands)

    Ruiz-Martinez, J.; Beale, A.M.; Deka, U.; O'Brien, M.G.; Quinn, P.D.; Mosselmans, J.F.W.; Weckhuysen, B.M.

    2013-01-01

    Fluid catalytic cracking (FCC) is the main conversion process used in oil refineries. An X-ray microscopy method is used to show that metal poisoning and related structural changes in the zeolite active material lead to a non-uniform core–shell deactivation of FCC catalyst particles. The study links

  9. 3D Nanoscale Chemical Imaging of the Distribution of Aluminum Coordination Environments in Zeolites with Soft X-Ray Microscopy

    NARCIS (Netherlands)

    Aramburo, Luis R.; Liu, Yijin; Tyliszczak, Tolek; de Groot, Frank M. F.; Andrews, Joy C.; Weckhuysen, Bert M.

    2013-01-01

    Here, we present the first nanoscale chemical imaging study revealing the spatial distribution of the amount and coordination environment of aluminum in zeolite materials with 3D scanning transmission X-ray microscopy (STXM). For this purpose, we have focused on two showcase samples involving the in

  10. Liquid crystal thermography as compared to X-ray diagnostics, clinical findings and capillary microscopy in sclerodermia progressiva

    Energy Technology Data Exchange (ETDEWEB)

    Loreck, D.; Buehler, G.; Brenke, A.; Schmidt, P.; Heerdegen, I.; Huege, H.

    1985-01-01

    The hands of 55 patients suffering from progressive sclerodermia were examined by liquid crystal thermography. The findings were compared with those of X-ray diagnosis and with clinical results. In 20 patients also capillary microscopy was applied. All patients revealed hypothermias in the fingers, independent from X-ray results, duration of the disease and Raynaud's phenomenon. Hypothermia could involve all fingers and was localized proximally or distally. In most of the patients also hyperthermias, not to be cooled, were found. They were diarthrodial and vasal, respectively.

  11. Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao [National Synchrotron Radiation Laboratory (China); Liu Yijin [School of Physics (China); Yue Zhengbo; Yu Hanqing [Laboratory of Environmental Engineering, School of Chemistry, University of Science and Technology of China, Hefei Anhui 230029 (China); Wang Chunru, E-mail: ychtian@ustc.edu.c [Institute of Chemistry, Chinese Academy of Sciences, Beijing 10060 (China)

    2009-09-01

    A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 {mu}m thickness and 4 {mu}m width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

  12. Investigation of lithiated carbons by transmission electron microscopy and x-ray diffraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tran, T D; Song, X Y; Kinoshita, K

    2000-10-26

    The microstructures of lithiated synthetic graphite and carbon black were studied by high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) analysis. Information about the crystal structure of carbon containing various Li compositions can provide useful insights to our understanding of the Li storage mechanism in carbonaceous materials. Samples with compositions of Li{sub 0.93}C{sub 6} or Li{sub 0.45}C{sub 6} were found to contain both stage-one and stage-two compounds. These observations are consistent with XRD data. The changes in sample microstructure as the results of lithiation and exposure to electron irradiation were observed by TEM and recorded over several minutes in the microscope environment. Selected area electron diffraction patterns indicated that the lithiated samples quickly changed composition to LiC{sub 24}, which appeared to dominate during the brief analysis period. The layer planes in the lattice image of a disordered carbon black after Li insertion are poorly defined, and changes in the microstructure of these lithiated carbons was not readily apparent. Observations on these lithium intercalation compounds as well as the limitation of the experimental procedure will be presented.

  13. 3D Analysis of Porosity in a Ceramic Coating Using X-ray Microscopy

    Science.gov (United States)

    Klement, Uta; Ekberg, Johanna; Kelly, Stephen T.

    2017-02-01

    Suspension plasma spraying (SPS) is a new, innovative plasma spray technique using a feedstock consisting of fine powder particles suspended in a liquid. Using SPS, ceramic coatings with columnar microstructures have been produced which are used as topcoats in thermal barrier coatings. The microstructure contains a wide pore size range consisting of inter-columnar spacings, micro-pores and nano-pores. Hence, determination of total porosity and pore size distribution is a challenge. Here, x-ray microscopy (XRM) has been applied for describing the complex pore space of the coatings because of its capability to image the (local) porosity within the coating in 3D at a resolution down to 50 nm. The possibility to quantitatively segment the analyzed volume allows analysis of both open and closed porosity. For an yttria-stabilized zirconia coating with feathery microstructure, both open and closed porosity were determined and it could be revealed that 11% of the pore volumes (1.4% of the total volume) are closed pores. The analyzed volume was reconstructed to illustrate the distribution of open and closed pores in 3D. Moreover, pore widths and pore volumes were determined. The results on the complex pore space obtained by XRM are discussed in connection with other porosimetry techniques.

  14. Scanning transmission X-ray microscopy as a speciation tool for natural organic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Rothe, J.; Plaschke, M.; Denecke, M.A. [Inst. fuer Nukleare Entsorgung, Forschungszentrum Karlsruhe, Karlsruhe (Germany)

    2004-07-01

    A molecular-scale understanding of the basic processes affecting stability and transport behavior of actinide cations, complexes or hydroxide ('eigencolloid') species is prerequisite to performance assessment of nuclear waste disposal in geological formations. Depending on their functional group chemistry and macromolecular structure, naturally occurring organic molecules (NOM) possess a high tendency towards actinide complexation reactions. However, the compositional and structural heterogeneity of NOM and mixed aggregates with inorganic phases makes speciation by spectromicroscopy techniques highly desirable. The applicability of Scanning Transmission X-ray Microscopy (STXM) as a speciation tool for the characterization of NOM is demonstrated for a multifunctional natural organic acid (chlorogenic acid), Eu(III)-loaded humic acid (HA) aggregates and Eu(III)-oxo/hydroxide/HA hetero-aggregates. It is shown that in situ probing of HA functional group chemistry down to a spatial resolution < 100 nm (i.e., less than femto-liter sampled volumes) is feasible, at the same time revealing morphological details on NOM aggregates and NOM/mineral associations. (orig.)

  15. Surface characterization of ginger powder examined by X-ray photoelectron spectroscopy and scanning electron microscopy.

    Science.gov (United States)

    Zhao, Xiaoyan; Ao, Qiang; Du, Fangling; Zhu, Junqing; Liu, Jie

    2010-09-01

    The surface composition of five types of ginger powders with the particle sizes of 300, 149, 74, 37 and 8.34 microm was investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and various types of physical-chemical characteristics regarding material particle size distributions, discoloration and chemical composition. The results show that the color differences are greater for superfine ground ginger than for conventional comminuted ones; the values of crude fibre, neutral detergent fiber (NDF) and acid detergent fiber (ADF) decrease with decreasing ginger particle size. However, no relationship with the surface fat, crude protein, ash and total solids exists. With superfine grinding the XPS O/C ratios of the five ginger powders were similar since the surfaces were not oxidized. Correlations were observed between the XPS N/C ratios and the high resolution XPS N 1s spectra. SEM observations revealed that the surface of ginger powder with a particle size of 300 microm is rougher, while superfine ground powders with particle sizes of 149, 74, 37 and 8.34 microm are similar to each other. This roughness difference between these surfaces correlates with the differences in their O/C ratios and the surface morphology of five ginger powders. Copyright 2010 Elsevier B.V. All rights reserved.

  16. Quantitative comparison of preparation methodologies for X-ray fluorescence microscopy of brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    James, Simon A.; Sexton, Brett A.; Hoobin, Pamela; Mayo, Sheridan C. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); Myers, Damian E. [St. Vincent s Hospital, Department of Surgery/Orthopaedics, Fitzroy, VIC (Australia); University of Melbourne, Department of Surgery, Parkville, VIC (Australia); Jonge, Martin D. de; Paterson, David; Howard, Daryl L. [Australian Synchrotron, Clayton, VIC (Australia); Vogt, Stefan [Argonne National Laboratory, X-ray Science Division, Argonne, IL (United States); Ryan, Chris G. [CSIRO, Earth Science and Resources Engineering, Clayton, VIC (Australia); University of Melbourne, School of Physics, Parkville, VIC (Australia); University of Tasmania, CODES Centre of Excellence, Hobart, TAS (Australia); Altissimo, Matteo [Melbourne Centre for Nanofabrication, Clayton, VIC (Australia); Moorhead, Gareth F. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); University of Melbourne, School of Physics, Parkville, VIC (Australia); Wilkins, Stephen W. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); Monash University, School of Physics, Clayton, VIC (Australia)

    2011-08-15

    X-ray fluorescence microscopy (XFM) facilitates high-sensitivity quantitative imaging of trace metals at high spatial resolution over large sample areas and can be applied to a diverse range of biological samples. Accurate determination of elemental content from recorded spectra requires proper calibration of the XFM instrument under the relevant operating conditions. Here, we describe the manufacture, characterization, and utilization of multi-element thin-film reference foils for use in calibration of XFM measurements of biological and other specimens. We have used these internal standards to assess the two-dimensional distribution of trace metals in a thin tissue section of a rat hippocampus. The data used in this study was acquired at the XFM beamline of the Australian Synchrotron using a new 384-element array detector (Maia) and at beamline 2-ID-E at the Advanced Photon Source. Post-processing of samples by different fixation techniques was investigated, with the conclusion that differences in solvent type and sample handling can significantly alter elemental content. The present study highlights the quantitative capability, high statistical power, and versatility of the XFM technique for mapping trace metals in biological samples, e.g., brain tissue samples in order to help understand neurological processes, especially when implemented in conjunction with a high-performance detector such as Maia. (orig.)

  17. In situ alkali-silica reaction observed by x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kurtis, K.E.; Monteiro, P.J.M. [Univ. of California, Berkeley, CA (United States); Brown, J.T.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    In concrete, alkali metal ions and hydroxyl ions contributed by the cement and reactive silicates present in aggregate can participate in a destructive alkali-silica reaction (ASR). This reaction of the alkalis with the silicates produces a gel that tends to imbibe water found in the concrete pores, leading to swelling of the gel and eventual cracking of the affected concrete member. Over 104 cases of alkali-aggregate reaction in dams and spillways have been reported around the world. At present, no method exists to arrest the expansive chemical reaction which generates significant distress in the affected structures. Most existing techniques available for the examination of concrete microstructure, including ASR products, demand that samples be dried and exposed to high pressure during the observation period. These sample preparation requirements present a major disadvantage for the study of alkali-silica reaction. Given the nature of the reaction and the affect of water on its products, it is likely that the removal of water will affect the morphology, creating artifacts in the sample. The purpose of this research is to observe and characterize the alkali-silica reaction, including each of the specific reactions identified previously, in situ without introducing sample artifacts. For observation of unconditioned samples, x-ray microscopy offers an opportunity for such an examination of the alkali-silica reaction. Currently, this investigation is focusing on the effect of calcium ions on the alkali-silica reaction.

  18. 3rd International Multidisciplinary Microscopy and Microanalysis Congress

    CERN Document Server

    Oral, Zehra

    2017-01-01

    The 3rd International Multidisciplinary Microscopy Congress (InterM2015), held from 19 to 23 October 2015, focused on the latest developments concerning applications of microscopy in the biological, physical and chemical sciences at all dimensional scales, advances in instrumentation, techniques in and educational materials on microscopy. These proceedings gather 17 peer-reviewed technical papers submitted by leading academic and research institutions from nine countries and representing some of the most cutting-edge research available.

  19. Ultrastructural imaging and molecular modeling of live bacteria using soft x-ray contact microscopy with nanoseconds laser-plasma radiation

    Science.gov (United States)

    Kado, Masataka; Richardson, Martin C.; Gaebel, Kai; Torres, David S.; Rajyaguru, Jayshree; Muszynski, Michael J.

    1995-09-01

    X-ray images of the various live bacteria, such as Staphylococcus and Streptococcus, and micromolecule such as chromosomal DNA from Escherichis coli, and Lipopolysacchride from Burkholderia cepacia, are obtained with soft x-ray contact microscopy. A compact tabletop type glass laser system is used to produce x-rays from Al, Si, and Au targets. The PMMA photoresists are used to record x-ray images. An AFM (atomic force microscope) is used to reproduce the x-ray images from the developed photoresists. The performance of the 50nm spatial resolutions are achieved and images are able to be discussed on the biological view.

  20. Feasibility tests of transmission x-ray photoelectron emission microscopy of wet samples

    Science.gov (United States)

    De Stasio, Gelsomina; Gilbert, B.; Nelson, T.; Hansen, R.; Wallace, J.; Mercanti, D.; Capozi, M.; Baudat, P. A.; Perfetti, P.; Margaritondo, G.; Tonner, B. P.

    2000-01-01

    We performed feasibility tests of photoelectron emission spectromicroscopy of wet samples in the water window (285-532 eV) soft x-ray spectral region. Water was successfully confined in an ultrahigh vacuum compatible compartment with x-ray transparent sides. This water cell was placed in the MEPHISTO spectromicroscope in a transmission geometry, and complete x-ray absorption spectra of the water window region were acquired. We also show micrographs of test samples, mounted outside of the compartment, and imaged through the water. This technique can be used to study liquid chemistry and, at least to the micron level, the microstructure of wet samples. Possibilities include cells in water or buffer, proteins in solution, oils of tribological interest, liquid crystals, and other samples not presently accessible to the powerful x-ray photoelectron emission spectromicroscopy technique.

  1. Correlating properties and microstructure of YBCO thin films by magnetic X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ruoss, Stephen; Stahl, Claudia; Weigand, Markus; Schuetz, Gisela [Max-Planck-Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart (Germany); Zahn, Patrick; Bayer, Jonas [Max-Planck-Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart (Germany); Research Institute for Innovative Surfaces, FINO, Aalen University, Beethovenstrasse 1, 73430 Aalen (Germany); Albrecht, Joachim [Research Institute for Innovative Surfaces, FINO, Aalen University, Beethovenstrasse 1, 73430 Aalen (Germany)

    2016-07-01

    The magnetic flux distribution in high-temperature superconductors namely YBCO has been observed using a novel high-resolution technique based on the X-ray magnetic circular dichroism (XMCD). Therefore, a CoFeB layer is deposited on the superconductor which exhibits a strong XMCD-effect. X-ray absorption measurements with circular polarized radiation allows the analysis of the magnetic flux distribution in the superconductor via the soft-magnetic sensor layer [3,4]. In the total electron yield (TEY) mode of the scanning X-ray microscope (SXM) the surface structure and the magnetic domains can be imaged at the same time. Having obtained such high resolution images, the correlation of magnetic flux penetration and defect structure of YBCO thin films can be analyzed. The measurements have been performed at the scanning X-ray microscope MAXYMUS at Bessy II, HZB Berlin.

  2. PULSED CAPILLARY DISCHARGE CHARACTERIZATION FOR SOFT X-RAY MICROSCOPY APPLICATIONS

    OpenAIRE

    VALDIVIA LEIVA; MARIA PIA

    2011-01-01

    The hollow cathode capillary discharge is of great interest as a high brightness, short pulse soft x-ray source. This thesis presents work done in the development, modifications, and subsequent characterization of a compact plasma source comprised of a pulsed capillary discharge exploiting hollow cathode dynamics. The low inductance, low stored energy, source is optimized using optical, electrical, x-ray, and e-beam diagnostics. The effect of parameters on the capillary phys...

  3. Direct observation of unstained wet biological samples by scanning-electron generation X-ray microscopy.

    Science.gov (United States)

    Ogura, Toshihiko

    2010-01-01

    Analytical tools of nanometre-scale resolution are indispensable in the fields of biology, physics and chemistry. One suitable tool, the soft X-ray microscope, provides high spatial resolution of visible light for wet specimens. For biological specimens, X-rays of water-window wavelength between carbon (284 eV; 4.3 nm) and oxygen (540 eV; 2.3 nm) absorption edges provide high-contrast imaging of biological samples in water. Among types of X-ray microscope, the transmission X-ray microscope using a synchrotron radiation source with diffractive zone plates offers the highest spatial resolution, approaching 15-10nm. However, even higher resolution is required to measure proteins and protein complexes in biological specimens; therefore, a new type of X-ray microscope with higher resolution that uses a simple light source is desirable. Here we report a novel scanning-electron generation X-ray microscope (SGXM) that demonstrates direct imaging of unstained wet biological specimens. We deposited wet yeasts in the space between two silicon nitride (Si(3)N(4)) films. A scanning electron beam of accelerating voltage 5 keV and current 1.6 nA irradiates the titanium (Ti)-coated Si(3)N(4) film, and the soft X-ray signal from it is detected by an X-ray photodiode (PD) placed below the sample. The SGXM can theoretically achieve better than 5 nm resolution. Our method can be utilized easily for various wet biological samples of bacteria, viruses, and protein complexes.

  4. Soft X-ray Holographic Microscopy with Sub-micrometer Resolution

    Institute of Scientific and Technical Information of China (English)

    JIANG Shiping; GAO Hongyi; ZHANG Yuxuan; ZHANG Xinyi1CHEN Min; Jianwen; XU Zhizhan

    2001-01-01

    Gabor X-ray in-line holograms are recorded with a photoresist at Hefei National Synchrotron Radiation Laboratory. An Atomic Force Microscope (AFM) is used to read the X-ray holograms of minute granules recorded on photoresist PMMA. Digitized hologram is reconstructed by numerical method. The granules with a size less than 0.3 μm can be resolved in the reconstructed image. So the eatimated resolution reaches the level of suibmicrometer.

  5. WHOLE CELL TOMOGRAPHY/MOLECULAR BIOLOGY/STRUCTURAL BIOLOGY: Affordable x-ray microscopy with nanoscale resolution

    Energy Technology Data Exchange (ETDEWEB)

    Evans, James E.; Blackborow, Paul; Horne, Stephen J.; Gelb, Jeff

    2013-03-01

    Biological research spans 10 orders of magnitude from angstroms to meters. While electron microscopy can reveal structural details at most of these spatial length scales, transmission electron tomography only reliably reconstructs three-dimensional (3-D) volumes of cellular material with a spatial resolution between 1-5 nm from samples less than 500 nm thick1. Most biological cells are 2-30 times thicker than this threshold, which means that a cell must be cut into consecutive slices with each slice reconstructed individually in order to approximate the contextual information of the entire cell. Fortunately, due to a larger penetration depth2, X-ray computed tomography bypasses the need to physically section a cell and enables imaging of intact cells and tissues on the micrometer or larger scale with tens to hundreds of nanometer spatial resolution. While the technique of soft x-ray microscopy has been extensively developed in synchrotron facilities, advancements in laboratory x-ray source designs now increase its accessibility by supporting commercial systems suitable for a standard laboratory. In this paper, we highlight a new commercial compact cryogenic soft x-ray microscope designed for a standard laboratory setting and explore its capabilities for mesoscopic investigations of intact prokaryotic and eukaryotic cells.

  6. A Comparison of Image Quality Evaluation Techniques for Transmission X-Ray Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bolgert, Peter J; /Marquette U. /SLAC

    2012-08-31

    Beamline 6-2c at Stanford Synchrotron Radiation Lightsource (SSRL) is capable of Transmission X-ray Microscopy (TXM) at 30 nm resolution. Raw images from the microscope must undergo extensive image processing before publication. Since typical data sets normally contain thousands of images, it is necessary to automate the image processing workflow as much as possible, particularly for the aligning and averaging of similar images. Currently we align images using the 'phase correlation' algorithm, which calculates the relative offset of two images by multiplying them in the frequency domain. For images containing high frequency noise, this algorithm will align noise with noise, resulting in a blurry average. To remedy this we multiply the images by a Gaussian function in the frequency domain, so that the algorithm ignores the high frequency noise while properly aligning the features of interest (FOI). The shape of the Gaussian is manually tuned by the user until the resulting average image is sharpest. To automatically optimize this process, it is necessary for the computer to evaluate the quality of the average image by quantifying its sharpness. In our research we explored two image sharpness metrics, the variance method and the frequency threshold method. The variance method uses the variance of the image as an indicator of sharpness while the frequency threshold method sums up the power in a specific frequency band. These metrics were tested on a variety of test images, containing both real and artificial noise. To apply these sharpness metrics, we designed and built a MATLAB graphical user interface (GUI) called 'Blur Master.' We found that it is possible for blurry images to have a large variance if they contain high amounts of noise. On the other hand, we found the frequency method to be quite reliable, although it is necessary to manually choose suitable limits for the frequency band. Further research must be performed to design an

  7. X-ray and transmission electron microscopy structural characterization of multifunctional Perovskite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Boudard, M., E-mail: Michel.Boudard@grenoble-inp.fr [Laboratoire des Materiaux et du Genie Physique, Grenoble INP, CNRS(UMR 5628), MINATEC, 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 1 (France); Girardot, C. [Laboratoire des Materiaux et du Genie Physique, Grenoble INP, CNRS(UMR 5628), MINATEC, 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 1 (France); Schneider Electric Industries S.A.S., 37 Quai Paul Louis Merlin, 38050 Grenoble Cedex 9 (France); Ihzaz, N. [Laboratoire des Materiaux et du Genie Physique, Grenoble INP, CNRS(UMR 5628), MINATEC, 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 1 (France); Laboratoire de Physico-Chimie des Materiaux, Departement de Physique, Faculte des Sciences de Monastir, 5019 Monastir, Universite de Monastir (Tunisia); Pignard, S.; Rapenne, L.; Roussel, H. [Laboratoire des Materiaux et du Genie Physique, Grenoble INP, CNRS(UMR 5628), MINATEC, 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 1 (France); Bartasyte, A. [Laboratoire des Materiaux et du Genie Physique, Grenoble INP, CNRS(UMR 5628), MINATEC, 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 1 (France); P2M, Institut Jean Lamour, Nancy Universite, Bd. des Aiguillettes, 54506 Vandoeuvre-ls-Nancy cedex (France)

    2012-05-01

    Different multifunctional (PbTiO{sub 3}, Sm{sub 0.6}Nd{sub 0.4}NiO{sub 3}, NdMnO{sub 3}) thin films were grown by metalorganic chemical vapor deposition (MOCVD) technique on SrTiO{sub 3} and LaAlO{sub 3} substrates. Transmission electron microscopy (TEM) and X-ray diffraction measurements reveal that almost single crystalline thin films can be epitaxially grown on the top of substrates. The relationship between the crystallographic orientation of the films and those of the substrates were determined by reciprocal space mapping and TEM analyses. PbTi03 thin films appear to be under tensile or compressive strain according to the different mismatch of their cell parameter with those of the substrate. Relaxation mechanism as a function of the film thickness arises from coexistence of different type of domains and size and strain effect are analyzed. SmNiO{sub 3} thin films present diffuse scattering strikes and are less well organized when compared to PbTi0{sub 3} thin films. Different domains are observed as well as an additional parasitic phase close to NiO. Its regular distribution can be associated to reduced transport properties. Preliminary observations on NdMnO{sub 3} thin films shows that an amorphous phase is obtained during MOCVD that can be transformed in a single crystalline film by annealing. The films are under tensile or compressive strain according to the different mismatch of their cell parameter with those of the substrate. Magnetic properties are investigated.

  8. Nephila clavipes spider dragline silk microstructure studied by scanning transmission X-ray microscopy.

    Science.gov (United States)

    Rousseau, Marie-Eve; Hernández Cruz, Daniel; West, M Marcia; Hitchcock, Adam P; Pézolet, Michel

    2007-04-04

    Nephila clavipes dragline silk microstructure has been investigated by scanning transmission X-ray microscopy (STXM), a technique that allows quantitative mapping of the level of orientation of the peptide groups at high spatial resolution (<50 nm). Maps of the orientation parameter P2 have been derived for spider silk for the first time. Dragline silk presents a very fine microstructure in which small, highly oriented domains (average area of 1800 nm2, thus clearly bigger than individual beta-sheet crystallites) are dispersed in a dominant, moderately oriented matrix with several small unoriented domains. Our results also highlight the orientation of the noncrystalline fraction in silk, which has been underestimated in numerous structural models. No evidence of either a regular lamellar structure or any periodicity along the fiber was observed at this spatial resolution. The surface of fresh spider silk sections consists of a approximately 30-120 nm thick layer of highly oriented protein chains, which was found to vary with the reeling speed, where web building (0.5 cm/s) and lifeline (10 cm/s) spinning speeds were investigated. While the average level of orientation of the protein chains is unaffected by the spinning speed, STXM measurements clearly highlight microstructure differences. The slowpull fiber contains a larger fraction of highly oriented domains, while the protein chains are more homogeneously oriented in the fastpull fiber. In comparison, cocoon silk from the silkworm Bombyx mori presents a narrower orientation distribution. The strength-extensibility combination found in spider dragline silk is associated with its broad orientation distribution of highly interdigitated and unoriented domains.

  9. Imaging Spin Dynamics on the Nanoscale using X-Ray Microscopy

    Directory of Open Access Journals (Sweden)

    Hermann eStoll

    2015-04-01

    Full Text Available The dynamics of emergent magnetic quasiparticles, such as vortices, domain walls, and bubbles are studied by scanning transmission x-ray microscopy (STXM, combining magnetic (XMCD contrast with about 25 nm lateral resolution as well as 70 ps time resolution. Essential progress in the understanding of magnetic vortex dynamics is achieved by vortex core reversal observed by sub-GHz excitation of the vortex gyromode, either by ac magnetic fields or spin transfer torque. The basic switching scheme for this vortex core reversal is the generation of a vortex-antivortex pair. Much faster vortex core reversal is obtained by exciting azimuthal spin wave modes with (multi-GHz rotating magnetic fields or orthogonal monopolar field pulses in x and y direction, down to 45 ps in duration. In that way unidirectional vortex core reversal to the vortex core 'down' or 'up' state only can be achieved with switching times well below 100 ps. Coupled modes of interacting vortices mimic crystal properties. The individual vortex oscillators determine the properties of the ensemble, where the gyrotropic mode represents the fundamental excitation. By self-organized state formation we investigate distinct vortex core polarization configurations and understand these eigenmodes in an extended Thiele model. Analogies with photonic crystals are drawn. Oersted fields and spin-polarized currents are used to excite the dynamics of domain walls and magnetic bubbles. From the measured phase and amplitude of the displacement of domain walls we deduce the size of the non-adiabatic spin-transfer torque. For sensing applications, the displacement of domain walls is studied and a direct correlation between domain wall velocity and spin structure is found. Finally the synchronous displacement of multiple domain walls using perpendicular field pulses is demonstrated as a possible paradigm shift for magnetic memory and logic applications.

  10. Imaging Spin Dynamics on the Nanoscale using X-Ray Microscopy

    Science.gov (United States)

    Stoll, Hermann; Noske, Matthias; Weigand, Markus; Richter, Kornel; Krüger, Benjamin; Reeve, Robert; Hänze, Max; Adolff, Christian; Stein, Falk-Ulrich; Meier, Guido; Kläui, Mathias; Schütz, Gisela

    2015-04-01

    The dynamics of emergent magnetic quasiparticles, such as vortices, domain walls, and bubbles are studied by scanning transmission x-ray microscopy (STXM), combining magnetic (XMCD) contrast with about 25 nm lateral resolution as well as 70 ps time resolution. Essential progress in the understanding of magnetic vortex dynamics is achieved by vortex core reversal observed by sub-GHz excitation of the vortex gyromode, either by ac magnetic fields or spin transfer torque. The basic switching scheme for this vortex core reversal is the generation of a vortex-antivortex pair. Much faster vortex core reversal is obtained by exciting azimuthal spin wave modes with (multi-GHz) rotating magnetic fields or orthogonal monopolar field pulses in x and y direction, down to 45 ps in duration. In that way unidirectional vortex core reversal to the vortex core 'down' or 'up' state only can be achieved with switching times well below 100 ps. Coupled modes of interacting vortices mimic crystal properties. The individual vortex oscillators determine the properties of the ensemble, where the gyrotropic mode represents the fundamental excitation. By self-organized state formation we investigate distinct vortex core polarization configurations and understand these eigenmodes in an extended Thiele model. Analogies with photonic crystals are drawn. Oersted fields and spin-polarized currents are used to excite the dynamics of domain walls and magnetic bubbles. From the measured phase and amplitude of the displacement of domain walls we deduce the size of the non-adiabatic spin-transfer torque. For sensing applications, the displacement of domain walls is studied and a direct correlation between domain wall velocity and spin structure is found. Finally the synchronous displacement of multiple domain walls using perpendicular field pulses is demonstrated as a possible paradigm shift for magnetic memory and logic applications.

  11. Bimetallic Catalysts and Platinum Surfaces Studied by X-ray Absorption Spectroscopy and Scanning Tunnelling Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Roenning, Magnus

    2000-07-01

    Bimetallic catalyst systems used in Fischer-Tropsch synthesis (Co-Re/Al{sub 2}O{sub 3}) and in the naphtha reforming process (Pt-Re/Al{sub 2}O{sub 3}) have been studied in situ using X-ray absorption spectroscopy (EXAFS). Additionally, the adsorption of ethene on platinum single crystal surfaces has been investigated using scanning tunnelling microscopy. In situ EXAFS at the cobalt K absorption edge have been carried out at 450{sup o}C on the hydrogen reduction of a rhenium-promoted Co{sub 3}O{sub 4}/Al{sub 2}O{sub 3} catalyst. Reductions carried out using 100% hydrogen and 5% hydrogen in helium gave different results. Whereas the reduction using dilute hydrogen leads to bulk-like metallic cobalt particles (hcp or fcc), reaction with pure hydrogen yields a more dispersed system with smaller cobalt metal particles (< 40 A). The results are rationalised in terms of different degrees of reoxidation of cobalt by the higher and lower concentrations of water generated during the reduction of cobalt oxide by 100% and 5% hydrogen, respectively. Additionally, in both reduction protocols a small fraction (3 -4 wt%) of the cobalt content is randomly dispersed over the tetrahedral vacancies of the alumina support. This dispersion occurs during reduction and not calcination. The cobalt in these sites cannot be reduced at 450 {sup o}C. The local environments about the rhenium atoms in Co-Re/{gamma}-A1{sub 2}O{sub 3} catalyst after different reduction periods have been studied by X-ray absorption spectroscopy. A bimetallic catalyst containing 4.6 wt% cobalt and 2 wt% rhenium has been compared with a corresponding monometallic sample with 2 wt% rhenium on the same support. The rhenium L{sub III} EXAFS analysis shows that bimetallic particles are formed after reduction at 450{sup o}C with the average particle size being 10-15 A. Rhenium is shown to be reduced at a later stage than cobalt. The fraction of cobalt atoms entering the support obstructs the access to the support for the

  12. Bimetallic Catalysts and Platinum Surfaces Studied by X-ray Absorption Spectroscopy and Scanning Tunnelling Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Roenning, Magnus

    2000-07-01

    Bimetallic catalyst systems used in Fischer-Tropsch synthesis (Co-Re/Al{sub 2}O{sub 3}) and in the naphtha reforming process (Pt-Re/Al{sub 2}O{sub 3}) have been studied in situ using X-ray absorption spectroscopy (EXAFS). Additionally, the adsorption of ethene on platinum single crystal surfaces has been investigated using scanning tunnelling microscopy. In situ EXAFS at the cobalt K absorption edge have been carried out at 450{sup o}C on the hydrogen reduction of a rhenium-promoted Co{sub 3}O{sub 4}/Al{sub 2}O{sub 3} catalyst. Reductions carried out using 100% hydrogen and 5% hydrogen in helium gave different results. Whereas the reduction using dilute hydrogen leads to bulk-like metallic cobalt particles (hcp or fcc), reaction with pure hydrogen yields a more dispersed system with smaller cobalt metal particles (< 40 A). The results are rationalised in terms of different degrees of reoxidation of cobalt by the higher and lower concentrations of water generated during the reduction of cobalt oxide by 100% and 5% hydrogen, respectively. Additionally, in both reduction protocols a small fraction (3 -4 wt%) of the cobalt content is randomly dispersed over the tetrahedral vacancies of the alumina support. This dispersion occurs during reduction and not calcination. The cobalt in these sites cannot be reduced at 450 {sup o}C. The local environments about the rhenium atoms in Co-Re/{gamma}-A1{sub 2}O{sub 3} catalyst after different reduction periods have been studied by X-ray absorption spectroscopy. A bimetallic catalyst containing 4.6 wt% cobalt and 2 wt% rhenium has been compared with a corresponding monometallic sample with 2 wt% rhenium on the same support. The rhenium L{sub III} EXAFS analysis shows that bimetallic particles are formed after reduction at 450{sup o}C with the average particle size being 10-15 A. Rhenium is shown to be reduced at a later stage than cobalt. The fraction of cobalt atoms entering the support obstructs the access to the support for the

  13. Piezo control for 1 nm spatial resolution synchrotron X-ray microscopy

    Science.gov (United States)

    Gofron, K. J.; Lauer, K.; Nazaretski, E.; Yan, H.; Kalbfleisch, S.; Greer, A.; Dalesio, B.; Chu, Y. S.

    2014-03-01

    A novel motion control system which utilizes the Power PMAC controller from Delta Tau Data Systems Inc., has been developed for positioning with 1 nm spatial resolution. Present work is a significant step forward towards commissioning of the X-ray microscope which will operate at the Hard X-ray Nanoprobe (HXN) beamline at the NSLS-II. The control system is capable of performing high-speed / high-accuracy on-the-fly scans of the sample with respect to the nano-focusing optics e.g. Multilayer Laue Lenses (MLL) or Fresnel X-ray Zone Plates (ZP) [1]. The Power PMAC controls piezoelectric-based nano-positioning stages using piezo-expansion for short range motion and stick-slip motion for longer travel distances. An EPICS interface to the Power PMAC has been developed allowing for easy integration into a beamline control environment.

  14. Defect-Assisted Hard-X-Ray Microscopy with Capillary Optics.

    Science.gov (United States)

    Korecki, Paweł; Sowa, Katarzyna M; Jany, Benedykt R; Krok, Franciszek

    2016-06-10

    Polycapillary x-ray focusing devices are built from hundreds of thousands of bent microcapillaries that are stacked into hexagonal arrays. We show that intrinsic point defects of the optics (e.g., missing or larger capillaries) lead to the formation of multiple x-ray images of an object positioned in the focal plane. These images can be recorded in parallel, and can provide spatial resolution that is limited by the defect size and not by the focal spot size. In a proof-of-principle experiment, we demonstrate submicron resolution, which has not yet been achieved with polycapillary focusing optics. Tailored optics with a controlled distribution of "defects" could be used for multimodal nanoscale x-ray imaging with laboratory setups.

  15. X-ray Phase Imaging Microscopy with Two-Dimensional Knife-Edge Filters

    Science.gov (United States)

    Choi, Jaeho; Park, Yong-Sung

    2012-04-01

    A novel scheme of X-ray differential phase imaging was implemented with an array source and a two-dimensional Foucault knife-edge (2DFK). A pinhole array lens was employed to manipulate the X-ray beam on the Fourier space. An emerging biaxial scanning procedure was also demonstrated with the periodic 2DFK. The differential phase images (DPIs) of the midrib in a leaf of a rose bush were visualized to verify the phase imaging of biological specimens by the proposed method. It also has features of depicting multiple-stack phase images, and rendering morphological DPIs, because it acquires pure phase information.

  16. Genetically targeted 3D visualisation of Drosophila neurons under Electron Microscopy and X-Ray Microscopy using miniSOG

    Science.gov (United States)

    Ng, Julian; Browning, Alyssa; Lechner, Lorenz; Terada, Masako; Howard, Gillian; Jefferis, Gregory S. X. E.

    2016-01-01

    Large dimension, high-resolution imaging is important for neural circuit visualisation as neurons have both long- and short-range patterns: from axons and dendrites to the numerous synapses at terminal endings. Electron Microscopy (EM) is the favoured approach for synaptic resolution imaging but how such structures can be segmented from high-density images within large volume datasets remains challenging. Fluorescent probes are widely used to localise synapses, identify cell-types and in tracing studies. The equivalent EM approach would benefit visualising such labelled structures from within sub-cellular, cellular, tissue and neuroanatomical contexts. Here we developed genetically-encoded, electron-dense markers using miniSOG. We demonstrate their ability in 1) labelling cellular sub-compartments of genetically-targeted neurons, 2) generating contrast under different EM modalities, and 3) segmenting labelled structures from EM volumes using computer-assisted strategies. We also tested non-destructive X-ray imaging on whole Drosophila brains to evaluate contrast staining. This enabled us to target specific regions for EM volume acquisition. PMID:27958322

  17. Small angle X-ray scattering and transmission electron microscopy study of the Lactobacillus brevis S-layer protein

    Science.gov (United States)

    Jääskeläinen, Pentti; Engelhardt, Peter; Hynönen, Ulla; Torkkeli, Mika; Palva, Airi; Serimaa, Ritva

    2010-10-01

    The structure of self-assembly domain containing recombinant truncation mutants of Lactobacillus brevis surface layer protein SlpA in aqueous solution was studied using small-angle X-ray scattering and transmission electron microscopy. The proteins were found out to interact with each other forming stable globular oligomers of about 10 monomers. The maximum diameter of the oligomers varied between 75 Å and 435 Å.

  18. Small angle X-ray scattering and transmission electron microscopy study of the Lactobacillus brevis S-layer protein

    Energy Technology Data Exchange (ETDEWEB)

    Jaeaeskelaeinen, Pentti [Department of Biomedical Engineering and Computational Science, PO Box 2200, FI-02015 Aalto University School of Science and Technology (Finland); Engelhardt, Peter [Haartman Institute, Department of Pathology, PO Box 21, FIN-00014 University of Helsinki (Finland); Hynoenen, Ulla; Palva, Airi [Department of Basic Veterinary Sciences, Division of Microbiology, FIN-00014 University of Helsinki (Finland); Torkkeli, Mika; Serimaa, Ritva, E-mail: ritva.serimaa@helsinki.f [Department of Physics, POB 64, 00014 University of Helsinki (Finland)

    2010-10-01

    The structure of self-assembly domain containing recombinant truncation mutants of Lactobacillus brevis surface layer protein SlpA in aqueous solution was studied using small-angle X-ray scattering and transmission electron microscopy. The proteins were found out to interact with each other forming stable globular oligomers of about 10 monomers. The maximum diameter of the oligomers varied between 75 A and 435 A.

  19. Austenite nucleation and growth observed on the level of individual grains by three-dimensional X-ray diffraction microscopy

    OpenAIRE

    Savran, V.I.; Offerman, S. E.; Sietsma, J.

    2010-01-01

    Austenite nucleation and growth is studied during continuous heating using three-dimensional X-ray diffraction (3-D XRD) microscopy at the European Synchrotron Radiation Facility (ESRF) (Grenoble, France). Unique in-situ observations of austenite nucleation and growth kinetics were made for two commercial medium-carbon low-alloy steels (0.21 and 0.35 wt pct carbon with an initial microstructure of ferrite and pearlite). The measured austenite volume fraction as a function of temperature shows...

  20. In situ spatial and time-resolved studies of electrochemical reactions by scanning transmission X-ray microscopy.

    Science.gov (United States)

    Guay, Daniel; Stewart-Ornstein, Jacob; Zhang, Xuerong; Hitchcock, Adam P

    2005-06-01

    The first in situ measurements with scanning transmission X-ray microscopy (STXM) of an active electrochemical cell are reported. An electrochemical wet cell, consisting of an electrodeposited polyaniline thin film on a thin Au film covered by an overlayer of 1 M HCl solution sitting between two X-ray transparent silicon nitride windows, was assembled. X-ray absorption images and spatial and time-resolved spectra of this system under potential control were examined using the beamline 5.3.2 STXM at the Advanced Light Source. The chemical state of the polyaniline film was reversibly converted between reduced (leucoemeraldine) and oxidized (emeraldine chloride) states by changing the applied potential. The electrochemical changes were monitored by spatially resolved C 1s and N 1s X-ray absorption spectroscopy and chemical-state selective imaging. Comparison of differences between images at two energies at different potentials provided electrochemical contrast with a resolution better than 50 nm, thereby monitoring that component of the polyaniline film that was electrochemically active. Kinematic studies in the subsecond regime are demonstrated.

  1. Laboratory-Based Cryogenic Soft X-ray Tomography with Correlative Cryo-Light and Electron Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, David B.; Gelb, Jeff; Palshin, Vadim; Evans, James E.

    2013-02-01

    Here we present a novel laboratory-based cryogenic soft X-ray microscope for whole cell tomography of frozen hydrated samples. We demonstrate the capabilities of this compact cryogenic microscope by visualizing internal sub-cellular structures of Saccharomyces cerevisiae cells. The microscope is shown to achieve better than 50 nm spatial resolution with a Siemens star test sample. For whole biological cells, the microscope can image specimens up to 5 micrometers thick. Structures as small as 90 nm can be detected in tomographic reconstructions at roughly 70 nm spatial resolution following a low cumulative radiation dose of only 7.2 MGy. Furthermore, the design of the specimen chamber utilizes a standard sample support that permits multimodal correlative imaging of the exact same unstained yeast cell via cryo-fluorescence light microscopy, cryo-soft x-ray microscopy and cryo-transmission electron microscopy. This completely laboratory-based cryogenic soft x-ray microscope will therefore enable greater access to three-dimensional ultrastructure determination of biological whole cells without chemical fixation or physical sectioning.

  2. X-Ray Absorption with Transmission X-Ray Microscopes

    NARCIS (Netherlands)

    de Groot, F.M.F.

    2016-01-01

    In this section we focus on the use of transmission X-ray microscopy (TXM) to measure the XAS spectra. In the last decade a range of soft X-ray and hard X-ray TXM microscopes have been developed, allowing the measurement of XAS spectra with 10–100 nm resolution. In the hard X-ray range the TXM

  3. Transmission electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1984-01-01

    The aim of this book is to outline the physics of image formation, electron­ specimen interactions and image interpretation in transmission electron mic­ roscopy. The book evolved from lectures delivered at the University of Munster and is a revised version of the first part of my earlier book Elek­ tronenmikroskopische Untersuchungs- und Priiparationsmethoden, omitting the part which describes specimen-preparation methods. In the introductory chapter, the different types of electron microscope are compared, the various electron-specimen interactions and their applications are summarized and the most important aspects of high-resolution, analytical and high-voltage electron microscopy are discussed. The optics of electron lenses is discussed in Chapter 2 in order to bring out electron-lens properties that are important for an understanding of the function of an electron microscope. In Chapter 3, the wave optics of elec­ trons and the phase shifts by electrostatic and magnetic fields are introduced; Fresne...

  4. Focused ion beam patterned Fe thin films A study by selective area Stokes polarimetry and soft x-Ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cook, P. J.; Shen, T. H.; Grundy, P. J.; Im, M.-Y.; Fischer, P.; Morton, S. A.; Kilcoyne, A. L. D.

    2010-11-14

    We demonstrate the potential to modify the magnetic behavior and structural properties of ferromagnetic thin films using focused ion beam 'direct-write' lithography. Patterns inspired by the split-ring resonators often used as components in meta-materials were defined upon 15 nm Fe films using a 30 keV Ga{sup +} focused ion beam at a dose of 2 x 10{sup 16} ions cm{sup -2}. Structural, chemical and magnetic changes to the Fe were studied using transmission soft X-ray microscopy at the ALS, Berkeley CA. X-ray absorption spectra showed a 23% reduction in the thickness of the film in the Ga irradiated areas, but no chemical change to the Fe was evident. X-ray images of the magnetic reversal process show domain wall pinning around the implanted areas, resulting in an overall increase in the coercivity of the film. Transmission electron microscopy showed significant grain growth in the implanted regions.

  5. Soft x-ray microscopy - a powerful analytical tool to image magnetism down to fundamental length and times scales

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Peter

    2008-08-01

    The magnetic properties of low dimensional solid state matter is of the utmost interest both scientifically as well as technologically. In addition to the charge of the electron which is the base for current electronics, by taking into account the spin degree of freedom in future spintronics applications open a new avenue. Progress towards a better physical understanding of the mechanism and principles involved as well as potential applications of nanomagnetic devices can only be achieved with advanced analytical tools. Soft X-ray microscopy providing a spatial resolution towards 10nm, a time resolution currently in the sub-ns regime and inherent elemental sensitivity is a very promising technique for that. This article reviews the recent achievements of magnetic soft X-ray microscopy by selected examples of spin torque phenomena, stochastical behavior on the nanoscale and spin dynamics in magnetic nanopatterns. The future potential with regard to addressing fundamental magnetic length and time scales, e.g. imaging fsec spin dynamics at upcoming X-ray sources is pointed out.

  6. 2D X-ray and FTIR micro-analysis of the degradation of cadmium yellow pigment in paintings of Henri Matisse

    NARCIS (Netherlands)

    Pouyet, E.; Cotte, M.; Fayard, B.; Salomé, M.; Meirer, F.; Mehta, A.; Uffelman, E. S.; Hull, A.; Vanmeert, F.; Kieffer, J.; Burghammer, M.; Janssens, K.; Sette, F.; Mass, J.

    2015-01-01

    The chemical and physical alterations of cadmium yellow (CdS) paints in Henri Matisse’s The Joy of Life (1905–1906, The Barnes Foundation) have been recognized since 2006, when a survey by portable X-ray fluorescence identified this pigment in all altered regions of the monumental painting. This

  7. Studies of SmCo5/Fe nanocomposite magnetic bilayers with magnetic soft x-ray transmission microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shahzad, F.; Siddiqi, S. A.; Im, M.-Y.; Avallone, A.; Fischer, P.; Hussain, Z.; Siddiqi, I.; Hellman, F.; Zhao, J.

    2009-12-04

    A hard/soft SmCo{sub 5}/Fe nanocomposite magnetic bilayer system has been fabricated on X-ray transparent 100-200 nm thin Si{sub 3}N{sub 4} membranes by magnetron sputtering. The microscopic magnetic domain pattern and its behavior during magnetization reversal in the hard and soft magnetic phases have been individually studied by element specific magnetic soft x-ray microscopy at a spatial resolution of better than 25nm. We observe that the domain patterns for soft and hard phases switch coherently throughout the full hysteresis cycle upon applying external magnetic fields. We derived local M(H) curves from the images for Fe and SmCo5 separately and found switching for both hard and soft phases same.

  8. The architecture of amyloid-like peptide fibrils revealed by X-ray scattering, diffraction and electron microscopy

    DEFF Research Database (Denmark)

    Langkilde, Annette Eva; Morris, Kyle L; Serpell, Louise C

    2015-01-01

    Structural analysis of protein fibrillation is inherently challenging. Given the crucial role of fibrils in amyloid diseases, method advancement is urgently needed. A hybrid modelling approach is presented enabling detailed analysis of a highly ordered and hierarchically organized fibril...... of the GNNQQNY peptide fragment of a yeast prion protein. Data from small-angle X-ray solution scattering, fibre diffraction and electron microscopy are combined with existing high-resolution X-ray crystallographic structures to investigate the fibrillation process and the hierarchical fibril structure...... hierarchical layer is generated via the pairing of ribbons during fibril maturation. Based on the complementary data, a quasi-atomic resolution model of the protofilament peptide arrangement is suggested. The peptide structure appears in a β-sheet arrangement reminiscent of the β-zipper structures evident from...

  9. Penetrating view of nano-structures in Aleochara verna spermatheca and flagellum by hard X-ray microscopy

    Institute of Scientific and Technical Information of China (English)

    Zhang Kai; Li De-E; Hong You-Li; Zhu Pei-Ping; Yuan Qing-Xi; Huang Wan-Xia; Gao Kun

    2013-01-01

    A penetrating view of the three-dimensional nanostructure of female spermatheca and male flagellum in the species Aleochara verna is obtained with 100-nm resolution using a hard X-ray microscope,which provides a fast noninvasive imaging technology for insect morphology.Through introducing Zernike phase contrast and heavy metal staining,images taken at 8 keV displayed sufficient contrast for observing nanoscale fine structures,such as the spermatheca cochleate duct and the subapex of the flagellum,which have some implications for the study of the sperm transfer process and genital evolution in insects.This work shows that both the spatial resolution and the contrast characteristic of hard X-ray microscopy are quite promising for insect morphology studies and,particularly,provide an attractive alternative to the destructive techniques used for investigating internal soft tissues.

  10. Composition measurement in substitutionally disordered materials by atomic resolution energy dispersive X-ray spectroscopy in scanning transmission electron microscopy.

    Science.gov (United States)

    Chen, Z; Taplin, D J; Weyland, M; Allen, L J; Findlay, S D

    2016-10-21

    The increasing use of energy dispersive X-ray spectroscopy in atomic resolution scanning transmission electron microscopy invites the question of whether its success in precision composition determination at lower magnifications can be replicated in the atomic resolution regime. In this paper, we explore, through simulation, the prospects for composition measurement via the model system of AlxGa1-xAs, discussing the approximations used in the modelling, the variability in the signal due to changes in configuration at constant composition, and the ability to distinguish between different compositions. Results are presented in such a way that the number of X-ray counts, and thus the expected variation due to counting statistics, can be gauged for a range of operating conditions.

  11. Uranium aerosols at a nuclear fuel fabrication plant: Characterization using scanning electron microscopy and energy dispersive X-ray spectroscopy

    Science.gov (United States)

    Hansson, E.; Pettersson, H. B. L.; Fortin, C.; Eriksson, M.

    2017-05-01

    Detailed aerosol knowledge is essential in numerous applications, including risk assessment in nuclear industry. Cascade impactor sampling of uranium aerosols in the breathing zone of nuclear operators was carried out at a nuclear fuel fabrication plant. Collected aerosols were evaluated using scanning electron microscopy and energy dispersive X-ray spectroscopy. Imaging revealed remarkable variations in aerosol morphology at the different workshops, and a presence of very large particles (up to ≅ 100 × 50 μm2) in the operator breathing zone. Characteristic X-ray analysis showed varying uranium weight percentages of aerosols and, frequently, traces of nitrogen, fluorine and iron. The analysis method, in combination with cascade impactor sampling, can be a powerful tool for characterization of aerosols. The uranium aerosol source term for risk assessment in nuclear fuel fabrication appears to be highly complex.

  12. X-ray diffraction and electron microscopy data for amyloid formation of Aβ40 and Aβ42

    Directory of Open Access Journals (Sweden)

    Olga M. Selivanova

    2016-09-01

    Full Text Available The data presented in this article are related to the research article entitled “One of the possible mechanisms of amyloid fibrils formation based on the sizes of primary and secondary folding nuclei of Aβ40 and Aβ42” (Dovidchenko et al., 2016 [1]. Aβ peptide is one of the most intensively studied amyloidogenic peptides. Despite the huge number of articles devoted to studying different fragments of Aβ peptide there are only several papers with correct kinetics data, also there are a few papers with X-ray data, especially for Aβ42. Our data present X-ray diffraction patterns both for Aβ40 and Aβ42 as well for Tris–HCl and wax. Moreover, our data provide kinetics of amyloid formation by recombinant Аβ40 and synthetic Аβ42 peptides by using electron microscopy.

  13. Workshop on the coupling of synchrotron radiation IR and X-rays with tip based scanning probe microscopies X-TIP

    Energy Technology Data Exchange (ETDEWEB)

    Comin, F.; Martinez-Criado, G.; Mundboth, K.; Susini, J. [European Synchrotron Radiation Facility (ESRF), 38 - Grenoble (France); Purans, J.; Sammelselg, V. [Tartu Univ. (Estonia); Chevrier, J.; Huant, S. [Universite Joseph-Fourier, Grenoble I, LEPES, 38 (France); Hamilton, B. [School of Electrical Engineering and Electronics, Manchester (United Kingdom); Saito, A. [Osaka Univ., RIKEN/SPring8 (Japan); Dhez, O. [OGG, INFM/CNR, 38 - Grenoble (France); Brocklesby, W.S. [Southampton Univ., Optoelectronics Research Centre (United Kingdom); Alvarez-Prado, L.M. [Ovieado, Dept. de Fisica (Spain); Kuzmin, A. [Institute of Solid State Physics - Riga (Latvia); Pailharey, D. [CRMC-N - CNRS, 13 - Marseille (France); Tonneau, D. [CRMCN - Faculte des sciences de Luminy, 13 - Marseille (France); Chretien, P. [Laboratoire de Genie Electrique de Paris, 75 - Paris (France); Cricenti, A. [ISM-CNR, Rome (Italy); DeWilde, Y. [ESPCI, 75 - Paris (France)

    2005-07-01

    The coupling of scanning probe microscopy (SPM) with synchrotron radiation is attracting increasing attention from nano-science community. By combining these 2 tools one can visualize, for example, the sample nano-structure prior to any X-ray characterization. Coupled with focusing devices or independently, SPM can provide spatial resolution below the optical limits. Furthermore, the possibility of employing SPM to manipulate nano-objects under X-ray beams is another exciting perspective. This document gathers the transparencies of 6 of the presentations made at the workshop: 1) the combination of atomic force microscopy and X-ray beam - experimental set-up and objectives; 2) the combination of scanning probe microscope and X-rays for detection of electrons; 3) towards soft X-ray scanning microscopy using tapered capillaries and laser-based high harmonic sources; 4) near-field magneto-optical microscopy; 5) near-field scanning optical microscopy - a brief overview -; and 6) from aperture-less near-field optical microscopy to infra-red near-field night vision. 4 posters entitled: 1) development of laboratory setup for X-ray/AFM experiments, 2) towards X-ray diffraction on single islands, 3) nano-XEOL using near-field detection, and 4) local collection with a STM tip of photoelectrons emitted by a surface irradiated by visible of UV laser beam, are included in the document.

  14. Use of fractal zone plates for transmission X-ray microscopy.

    Science.gov (United States)

    Ge, Xin; Wang, Zhili; Gao, Kun; Wang, Dajiang; Wu, Zhao; Chen, Jian; Pan, Zhiyun; Zhang, Kai; Hong, Youli; Zhu, Peiping; Wu, Ziyu

    2012-09-01

    In this contribution we discuss the possibility of designing a modified transmission X-ray microscope by using fractal zone plates (Fzps) as diffractive optical elements. In the modified transmission X-ray microscope optical layout, we first introduced a fractal zone plate as the microscope objective. Indeed, a fractal zone plate cannot only be used as an image-forming component but also as a condenser element to achieve an extended depth of field. Numerical analysis reveals that fractal zone plates and conventional Fresnel zone plates have similar imaging capabilities under different coherent illumination. Using a fractal zone plate as a condenser we also simulated axial irradiance. Results confirm that fractal zone plates can improve focusing capability with an extended depth of field. Although preliminary, these simulations clearly reveal that fractal zone plates, when available, will be of great help in microscope layouts, in particular for foreseen high-resolution applications in the "water window" as strongly required in biological research.

  15. Confocal soft X-ray scanning transmission microscopy: setup, alignment procedure and limitations

    OpenAIRE

    Späth, Andreas; Raabe, Jörg; Fink, Rainer H.

    2015-01-01

    Zone-plate-based scanning transmission soft X-ray microspectroscopy (STXM) is a well established technique for high-contrast imaging of sufficiently transparent specimens (e.g. ultrathin biological tissues, polymer materials, archaeometric specimens or magnetic thin films) with spatial resolutions in the regime of 20 nm and high spectroscopic or chemical sensitivity. However, due to the relatively large depth of focus of zone plates, the resolution of STXM along the optical axis so far stays ...

  16. Confocal soft X-ray scanning transmission microscopy: setup, alignment procedure and limitations.

    Science.gov (United States)

    Späth, Andreas; Raabe, Jörg; Fink, Rainer H

    2015-01-01

    Zone-plate-based scanning transmission soft X-ray microspectroscopy (STXM) is a well established technique for high-contrast imaging of sufficiently transparent specimens (e.g. ultrathin biological tissues, polymer materials, archaeometric specimens or magnetic thin films) with spatial resolutions in the regime of 20 nm and high spectroscopic or chemical sensitivity. However, due to the relatively large depth of focus of zone plates, the resolution of STXM along the optical axis so far stays unambiguously behind for thicker X-ray transparent specimens. This challenge can be addressed by the implementation of a second zone plate in the detection pathway of the beam, resulting in a confocal arrangement. Within this paper a first proof-of-principle study for a confocal STXM (cSTXM) and an elaborate alignment procedure in transmission and fluorescence geometry are presented. Based on first confocal soft X-ray micrographs of well known specimens, the advantage and limitation of cSTXM as well as further development potentials for future applications are discussed.

  17. Confocal soft X-ray scanning transmission microscopy: setup, alignment procedure and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Späth, Andreas [Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany); Raabe, Jörg [Paul Scherrer Institut, 5232 Villigen (Switzerland); Fink, Rainer H., E-mail: rainer.fink@fau.de [Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany); Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Egerlandstraße 3, 91058 Erlangen (Germany)

    2015-01-01

    A conventional STXM setup has been upgraded with a second micro zone plate and aligned to confocal geometry. Two confocal geometries (in-line and off-axis) have been evaluated and a discussion on prospects and limitations is presented. Zone-plate-based scanning transmission soft X-ray microspectroscopy (STXM) is a well established technique for high-contrast imaging of sufficiently transparent specimens (e.g. ultrathin biological tissues, polymer materials, archaeometric specimens or magnetic thin films) with spatial resolutions in the regime of 20 nm and high spectroscopic or chemical sensitivity. However, due to the relatively large depth of focus of zone plates, the resolution of STXM along the optical axis so far stays unambiguously behind for thicker X-ray transparent specimens. This challenge can be addressed by the implementation of a second zone plate in the detection pathway of the beam, resulting in a confocal arrangement. Within this paper a first proof-of-principle study for a confocal STXM (cSTXM) and an elaborate alignment procedure in transmission and fluorescence geometry are presented. Based on first confocal soft X-ray micrographs of well known specimens, the advantage and limitation of cSTXM as well as further development potentials for future applications are discussed.

  18. Revealing the hidden preliminary version of Eça de Queiroz “The Illustrious House of Ramires” using X-ray micro-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pessanha, S. [LIBPhys-UNL Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (Portugal); Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Campus Caparica (Portugal); Costa, M. [LIBPhys-UNL Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (Portugal); Sampaio, J.M. [BioISI – Biosystems & Integrative Sciences Institute, Lisboa (Portugal); Carvalho, M.L. [LIBPhys-UNL Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (Portugal); Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Campus Caparica (Portugal)

    2016-03-15

    An original manuscript of Eça de Queiroz (1845–1900) “The Illustrious House of Ramires”, published in 1900, was analyzed using high resolution X-ray Fluorescence imaging. Several words and sentences were canceled, as corrections for later versions. In two cases, however, almost half a page was covered with a new sheet of paper (glued) and rewritten. Taking advantage of the penetration power of the characteristic X-rays of the chromium present in the ink with which the text was written, we were able to reconstruct the sentences that were edited by the author. The images created, combined with paleographic expertise, will enable the discovery of the preliminary version of this classic of Portuguese literature.

  19. Revealing the hidden preliminary version of Eça de Queiroz "The Illustrious House of Ramires" using X-ray micro-analysis

    Science.gov (United States)

    Pessanha, S.; Costa, M.; Sampaio, J. M.; Carvalho, M. L.

    2016-03-01

    An original manuscript of Eça de Queiroz (1845-1900) "The Illustrious House of Ramires", published in 1900, was analyzed using high resolution X-ray Fluorescence imaging. Several words and sentences were canceled, as corrections for later versions. In two cases, however, almost half a page was covered with a new sheet of paper (glued) and rewritten. Taking advantage of the penetration power of the characteristic X-rays of the chromium present in the ink with which the text was written, we were able to reconstruct the sentences that were edited by the author. The images created, combined with paleographic expertise, will enable the discovery of the preliminary version of this classic of Portuguese literature.

  20. Structural studies of technetium-zirconium alloys by X-ray diffraction, high-resolution electron microscopy, and first-principles calculations.

    Science.gov (United States)

    Poineau, Frederic; Hartmann, Thomas; Weck, Philippe F; Kim, Eunja; Silva, G W Chinthaka; Jarvinen, Gordon D; Czerwinski, Kenneth R

    2010-02-15

    The structural properties of Tc-Zr binary alloys were investigated using combined experimental and computational approaches. The Tc(2)Zr and Tc(6)Zr samples were characterized by X-ray diffraction analysis, scanning electron microscopy, electron probe microanalysis, and transmission electron microscopy. Our XRD results show that Tc(6)Zr crystallizes in the cubic alpha-Mn-type structure (I43m space group) with a variable stoichiometry of Tc(6.25-x)Zr (0 Tc(2)Zr has a hexagonal crystal lattice with a MgZn(2)-type structure (P6(3)/mmc space group). Rietveld analysis of the powder XRD patterns and density functional calculations of the "Tc(6)Zr" phase show a linear increase of the lattice parameter when moving from Tc(6.25)Zr to Tc(4..80)Zr compositions, similar to previous observations in the Re-Zr system. This variation of the composition of "Tc(6)Zr" is explained by the substitution of Zr for Tc atoms in the 2a site of the alpha-Mn-type structure. These results suggest that the width of the "Tc(6)Zr" phase needs to be included when constructing the Tc-Zr phase diagram. The bonding character and stability of the various Tc-Zr phases were also investigated from first principles. Calculations indicate that valence and conduction bands near the Fermi level are dominated by electrons occupying the 4d orbital. In particular, the highest-lying molecular orbitals of the valence band of Tc(2)Zr are composed of d-d sigma bonds, oriented along the normal axis of the (110) plane and linking the Zr network to the Tc framework. Strong d-d bonds stabilizing the Tc framework in the hexagonal unit cell are also in the valence band. In the cubic structures of Tc-Zr phases, only Tc 4d orbitals are found to significantly contribute near the Fermi level.

  1. Synchrotron-based in situ soft X-ray microscopy of Ag corrosion in aqueous chloride solution

    Science.gov (United States)

    Bozzini, B.; D'Urzo, L.; Gianoncelli, A.; Kaulich, B.; Kiskinova, M.; Prasciolu, M.; Tadjeddine, A.

    2009-09-01

    In this paper we report an in situ X-ray microscopy study of a model metal electrochemistry system, incorporating faradaic reactivity: the anodic corrosion and cathodic electrodeposition of Ag in aqueous systems. The information at sub-μm scale about morpho-chemical evolution of the electrified interface, provided by this novel electroanalytical approach fosters fundamental understanding of important issues concerning material fabrication and stability, which are crucial in developing the next generation electrochemical technologies, such as fuel cells and biosensors. The key methodology challenge faced in this pilot electrochemical experiments is combining a three-electrode configuration and wet environment, which required metal electrodes suitable for transmitting soft X-rays and a sealed cell allowing working in high vacuum. This has been solved via lithographic fabrication route fabricating 75 nm thick Ag electrodes and using Si3N4 membranes as X-ray windows and electrode support. Imaging in the STXM mode with phase contrast allowed us to monitor the corrosion morphologies and metal outgrowth features. Localised thickness variation and the build-up of reaction products of electron density different from that of the starting material have been detected with high sensitivity.

  2. Synchrotron-based in situ soft X-ray microscopy of Ag corrosion in aqueous chloride solution

    Energy Technology Data Exchange (ETDEWEB)

    Bozzini, B; D' Urzo, L [Dipartimento di Ingegneria dell' Innovazione, Universita del Salento, via Monteroni, 73100 Lecce (Italy); Gianoncelli, A; Kaulich, B; Kiskinova, M [Sincrotrone Trieste S.C.p.A., ELETTRA, s.s. 14 km 163.5 in Area Science Park, 34012 Basovizza, Trieste (Italy); Prasciolu, M [CNR-INFM TASC National Laboratory S.S.14 Km 163.5, Area Science Park, 34012 Basovizza, Trieste (Italy); Tadjeddine, A, E-mail: alessandra.gianoncelli@elettra.trieste.i [3UDIL/CNRS, BP34 91898 Orsay Cedex (France)

    2009-09-01

    In this paper we report an in situ X-ray microscopy study of a model metal electrochemistry system, incorporating faradaic reactivity: the anodic corrosion and cathodic electrodeposition of Ag in aqueous systems. The information at sub-{mu}m scale about morpho-chemical evolution of the electrified interface, provided by this novel electroanalytical approach fosters fundamental understanding of important issues concerning material fabrication and stability, which are crucial in developing the next generation electrochemical technologies, such as fuel cells and biosensors. The key methodology challenge faced in this pilot electrochemical experiments is combining a three-electrode configuration and wet environment, which required metal electrodes suitable for transmitting soft X-rays and a sealed cell allowing working in high vacuum. This has been solved via lithographic fabrication route fabricating 75 nm thick Ag electrodes and using Si{sub 3}N{sub 4} membranes as X-ray windows and electrode support. Imaging in the STXM mode with phase contrast allowed us to monitor the corrosion morphologies and metal outgrowth features. Localised thickness variation and the build-up of reaction products of electron density different from that of the starting material have been detected with high sensitivity.

  3. Logarithmic 3-Band Color Encoding: Robust Method for Display and Comparison of Compositional Maps in Electron Probe X-ray Microanalysis

    Science.gov (United States)

    Newbury, Dale E.; Bright, David S.

    1999-10-01

    Electron-excited X-ray maps recorded with the scanning electron microscope (SEM)/electron probe X-ray microanalyzer (EPMA) are a major method of presenting compositional information. Digitally recorded maps are processed in a variety of ways to improve the visibility of features. Scaling of the recorded signal to match the 8-bit gray-scale intensity range of a typical computer display system is almost always necessary. Inherent limitations of gray-scale displays have led to other intensity-encoding methods for X-ray maps, including clipping, histogram normalization, and pseudocolor scales. While feature visibility is improved by applying these scales, comparisons among image sets are difficult. Quantitative comparisons must be based on standardized intensities corrected for background to produce intensity ratio (k-value) maps. We have developed a new logarithmic, multiband color-encoding method to view these k-value maps more effectively. Three color bands are defined, starting with a dark primary color and grading to a bright pastel: blue = trace (0.001 to 0.01); green = minor (0.01 to 0.1); and red = major (0.1 to 1.0). Within each band, the color is assigned according to a logarithmic scale that depends on intensity ratio or compositional measurements. Logarithmic multiband color encoding permits direct comparisons of maps, such as maps of different elements in the same field of view or maps of the same element in different areas, because the color scale is identical for all maps.

  4. Taking X-ray Diffraction to the Limit: Macromolecular Structures from Femtosecond X-ray Pulses and Diffraction Microscopy of Cells with Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, H N; Miao, J; Kirz, J; Sayre, D; Hodgson, K O

    2003-10-01

    The methodology of X-ray crystallography has recently been successfully extended to the structure determination of non-crystalline specimens. The phase problem was solved by using the oversampling method, which takes advantage of ''continuous'' diffraction pattern from non-crystalline specimens. Here we review the principle of this newly developed technique and discuss the ongoing experiments of imaging non-periodic objects, like cells and cellular structures using coherent and bright X-rays from the 3rd generation synchrotron radiation. In the longer run, the technique may be applied to image single biomolecules by using the anticipated X-ray free electron lasers. Computer simulations have so far demonstrated two important steps: (1) by using an extremely intense femtosecond X-ray pulse, a diffraction pattern can be recorded from a macromolecule before radiation damage manifests itself, and (2) the phase information can be ab initio retrieved from a set of calculated noisy diffraction patterns of single protein molecules.

  5. From virus structure to chromatin: X-ray diffraction to three-dimensional electron microscopy.

    Science.gov (United States)

    Klug, Aaron

    2010-01-01

    Early influences led me first to medical school with a view to microbiology, but I felt the lack of a deeper foundation and changed to chemistry, which in turn led me to physics and mathematics. I moved to the University of Cape Town to work on the X-ray crystallography of some small organic compounds. I developed a new method of using molecular structure factors to solve the crystal structure, which won me a research studentship to Trinity College Cambridge and the Cavendish Laboratory. There I worked on the austenite-pearlite transition in steel. This is governed by the dissipation of latent heat, and I ended up numerically solving partial differential equations. I used the idea of nucleation and growth during the phase change, which had its echo when I later tackled the assembly of Tobacco mosaic virus (TMV) from its constituent RNA and protein subunits. I wanted to move on to X-ray structure analysis of large biological molecules and obtained a Nuffield Fellowship to work in J.D. Bernal's department at Birkbeck College, London. There, I met Rosalind Franklin, who had taken up the study of TMV. I was able to interpret some of Franklin's beautiful X-ray diffraction patterns of the virus particle. From then on, my fate was sealed. After Franklin's untimely death in 1958, I moved in 1962 to the newly built MRC Laboratory of Molecular Biology in Cambridge, which, under Max Perutz, housed the original MRC unit from the Cavendish Laboratory. I was thus privileged to join the Laboratory at an early stage in its expansion and consequently able to take advantage of, and to help build up, its then unique environment of intellectual and technological sophistication. There I have remained ever since.

  6. Development of achromatic full-field x-ray microscopy with compact imaging mirror system

    Science.gov (United States)

    Matsuyama, S.; Emi, Y.; Kino, H.; Sano, Y.; Kohmura, Y.; Tamasaku, K.; Yabashi, M.; Ishikawa, T.; Yamauchi, K.

    2013-09-01

    Compact advanced Kirkpatrick-Baez optics are used to construct a microscope that is easy to align and robust against vibrations and thermal drifts. The entire length of the imaging mirror system is 286 mm, which is 34% shorter than the previous model. A spatial resolution test is performed in which magnified bright-field images of a pattern are taken with an X-ray camera at an energy of 10 keV at the BL29XUL beamline of SPring-8. A line-and-space pattern having a 50- nm width could be resolved, although the image contrast is low.

  7. 2D X-ray and FTIR micro-analysis of the degradation of cadmium yellow pigment in paintings of Henri Matisse

    Energy Technology Data Exchange (ETDEWEB)

    Pouyet, E. [European Synchrotron Radiation Facility, Grenoble (France); ARC-Nucleart - CEA/Grenoble, Grenoble Cedex 9 (France); Cotte, M. [European Synchrotron Radiation Facility, Grenoble (France); LAMS (Laboratoire d' Archeologie Moleculaire et Structurale) UMR-8220, Ivry-sur-Seine (France); Fayard, B.; Salome, M.; Kieffer, J.; Burghammer, M.; Sette, F. [European Synchrotron Radiation Facility, Grenoble (France); Meirer, F. [Utrecht University, Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht (Netherlands); Mehta, A. [SLAC National Accelerator Laboratory, Stanford Synchrotron radiation Lightsource, Menlo Park, CA (United States); Uffelman, E.S. [Washington and Lee University, Department of Chemistry and Biochemistry, Lexington, VA (United States); Hull, A. [University of Delaware, Department of Chemistry and Biochemistry, Newark, DE (United States); Vanmeert, F.; Janssens, K. [University of Antwerp, AXES Research Group, Department of Chemistry, Antwerp (Belgium); Mass, J. [Winterthur Museum, Scientific Research and Analysis Laboratory, Conservation Department, Winterthur, DE (United States)

    2015-11-15

    The chemical and physical alterations of cadmium yellow (CdS) paints in Henri Matisse's The Joy of Life (1905-1906, The Barnes Foundation) have been recognized since 2006, when a survey by portable X-ray fluorescence identified this pigment in all altered regions of the monumental painting. This alteration is visible as fading, discoloration, chalking, flaking, and spalling of several regions of light to medium yellow paint. Since that time, synchrotron radiation-based techniques including elemental and spectroscopic imaging, as well as X-ray scattering have been employed to locate and identify the alteration products observed in this and related works by Henri Matisse. This information is necessary to formulate one or multiple mechanisms for degradation of Matisse's paints from this period, and thus ensure proper environmental conditions for the storage and the display of his works. This paper focuses on 2D full-field X-ray Near Edge Structure imaging, 2D micro-X-ray Diffraction, X-ray Fluorescence, and Fourier Transform Infra-red imaging of the altered paint layers to address one of the long-standing questions about cadmium yellow alteration - the roles of cadmium carbonates and cadmium sulphates found in the altered paint layers. These compounds have often been assumed to be photo-oxidation products, but could also be residual starting reagents from an indirect wet process synthesis of CdS. The data presented here allow identifying and mapping the location of cadmium carbonates, cadmium chlorides, cadmium oxalates, cadmium sulphates, and cadmium sulphides in thin sections of altered cadmium yellow paints from The Joy of Life and Matisse's Flower Piece (1906, The Barnes Foundation). Distribution of various cadmium compounds confirms that cadmium carbonates and sulphates are photo-degradation products in The Joy of Life, whereas in Flower Piece, cadmium carbonates appear to have been a [(partially) unreacted] starting reagent for the yellow paint, a

  8. Characterization of a SiC/SiC composite by X-ray diffraction, atomic force microscopy and positron spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Brauer, G. [Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf e.V., PF 510119, D-01314 Dresden (Germany)]. E-mail: g.brauer@fz-rossendorf.de; Anwand, W. [Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf e.V., PF 510119, D-01314 Dresden (Germany); Eichhorn, F. [Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf e.V., PF 510119, D-01314 Dresden (Germany); Skorupa, W. [Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf e.V., PF 510119, D-01314 Dresden (Germany); Hofer, C. [Institut fuer Physik, Montanuniversitaet Leoben, Franz Josef Str. 18, A-8700 Leoben (Austria); Teichert, C. [Institut fuer Physik, Montanuniversitaet Leoben, Franz Josef Str. 18, A-8700 Leoben (Austria); Kuriplach, J. [Department of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, CZ-180 00 Prague (Czech Republic); Cizek, J. [Department of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, CZ-180 00 Prague (Czech Republic); Prochazka, I. [Department of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, CZ-180 00 Prague (Czech Republic); Coleman, P.G. [Department of Physics, University of Bath, Bath BA2 7 AY (United Kingdom); Nozawa, T. [Metals and Ceramics Division, Oak Ridge National Laboratory, P.O. Box 2008, MS6151, Oak Ridge, TN 37831-6151 (United States); Kohyama, A. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2006-02-28

    A SiC/SiC composite is characterized by X-ray diffraction, atomic force microscopy and various positron spectroscopies (slow positron implantation, positron lifetime and re-emission). It is found that besides its main constituent 3C-SiC the composite still must contain some graphite. In order to better interpret the experimental findings of the composite, a pyrolytic graphite sample was also investigated by slow positron implantation and positron lifetime spectroscopies. In addition, theoretical calculations of positron properties of graphite are presented.

  9. Structural Features of Nanocrystalline Magnetite Obtained by Different Syntheses According to X-Ray Diffraction and Electron Microscopy Data

    Directory of Open Access Journals (Sweden)

    A.N. Kalinkevich

    2011-01-01

    Full Text Available Structural features of nanosized magnetite Fe3O4 synthesized in the presence of polymeric matrices (polysaccharide chitosan, etc. were studied using transmission electron microscopy (TEM and X-ray diffraction analysis. The data obtained strongly suggest the influence of the polysaccharide matrix on the magnetite nanoparticles growth inhibition and size stabilization. The controlled size decrease of Fe3O4 nanoparticles is accompanied with the increase of crystal lattice imperfection and the decrease of the unit cell size. The utility of TEM and XRD complementary use for the determination of nanosized magnetite particles structure and substructure parameters is shown in the present paper.

  10. Measuring inside damage of individual multi-walled carbon nanotubes using scanning transmission X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jinyin; Bai, Lili; Zhao, Guanqi; Sun, Xuhui, E-mail: xhsun@suda.edu.cn, E-mail: jzhong@suda.edu.cn; Zhong, Jun, E-mail: xhsun@suda.edu.cn, E-mail: jzhong@suda.edu.cn [Soochow University-Western University Centre for Synchrotron Radiation Research, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123 (China); Wang, Jian [Canadian Light Source, Inc., University of Saskatchewan, Saskatoon, Saskatchewan S7N 0X4 (Canada)

    2014-06-16

    The electronic structure of individual multi-walled carbon nanotubes (MWCNTs) has been probed using scanning transmission X-ray microscopy (STXM). Although transmission electron microscope (TEM) images show that the exterior of the MWCNTs are clean and straight; the inside structure of some of the MWCNTs is much less well ordered, as revealed by STXM. The amorphization of the interior tubes can be introduced in the growth or modification processes. Moreover, TEM measurement with high dose may also lead to the inside damage. Our results reveal that the structure of individual MWCNTs can be complex and suggest that electronic structure measurements are an important tool for characterizing carbon nanomaterials.

  11. Measuring inside damage of individual multi-walled carbon nanotubes using scanning transmission X-ray microscopy

    Science.gov (United States)

    Liu, Jinyin; Bai, Lili; Wang, Jian; Zhao, Guanqi; Sun, Xuhui; Zhong, Jun

    2014-06-01

    The electronic structure of individual multi-walled carbon nanotubes (MWCNTs) has been probed using scanning transmission X-ray microscopy (STXM). Although transmission electron microscope (TEM) images show that the exterior of the MWCNTs are clean and straight; the inside structure of some of the MWCNTs is much less well ordered, as revealed by STXM. The amorphization of the interior tubes can be introduced in the growth or modification processes. Moreover, TEM measurement with high dose may also lead to the inside damage. Our results reveal that the structure of individual MWCNTs can be complex and suggest that electronic structure measurements are an important tool for characterizing carbon nanomaterials.

  12. Wide-field x-ray microscopy with Kirkpatrick-Baez optics

    Science.gov (United States)

    Jach, Terrence; Durbin, Stephen M.; Bakulin, Alex; Bright, David S.; Stagarescu, Cristian; Srajer, George; Haskel, Daniel; Pedulla, Joseph

    2001-12-01

    Modern technology permits the fabrication of Kirkpatrick-Baez (KB) multilayer optics with performance close to the theoretical limit. We have constructed a KB field-imaging microscope which operates in the x-ray energy range 6-10 keV with a field of view of 40-150 micrometers . The optics perform at a reflectivity of 80% at the first Bragg peak. Using highly-collimated synchrotron radiation, we realize a resolution of 900 nm at 9 keV. The intensity and magnification are sufficient to perform real-time imaging with a CCD x-ray camera, with increases in field of view and resolution at this energy due to improvements in both data collection and image processing. The collimation of the incident radiation corresponds to Koehler illumination. The dynamic range of the images using a 12-bit camera allows us to extend the field of view at the Bragg reflection over several Kiessig fringes. We have adjusted the energy to take advantage of absorption at the excitation edges of elements and have performed imaging using circularly polarized radiation. We have used this instrument to demonstrate wide-field imaging in both absorption and diffraction. We present magnified images of multiple layers in a test integrated circuit in absorption and of a metal single crystal in diffraction.

  13. In situ observation of Cu-Ni alloy nanoparticle formation by X-ray diffraction, X-ray absorption spectroscopy, and transmission electron microscopy: Influence of Cu/Ni ratio

    DEFF Research Database (Denmark)

    Wu, Qiongxiao; Duchstein, Linus Daniel Leonhard; Chiarello, Gian Luca

    2014-01-01

    Silica-supported, bimetallic Cu-Ni nanomaterials were prepared with different ratios of Cu to Ni by incipient wetness impregnation without a specific calcination step before reduction. Different in situ characterization techniques, in particular transmission electron microscopy (TEM), X-ray diffr......Silica-supported, bimetallic Cu-Ni nanomaterials were prepared with different ratios of Cu to Ni by incipient wetness impregnation without a specific calcination step before reduction. Different in situ characterization techniques, in particular transmission electron microscopy (TEM), X...

  14. A new detector system for low energy X-ray fluorescence coupled with soft X-ray microscopy: First tests and characterization

    Science.gov (United States)

    Gianoncelli, Alessandra; Bufon, Jernej; Ahangarianabhari, Mahdi; Altissimo, Matteo; Bellutti, Pierluigi; Bertuccio, Giuseppe; Borghes, Roberto; Carrato, Sergio; Cautero, Giuseppe; Fabiani, Sergio; Giacomini, Gabriele; Giuressi, Dario; Kourousias, George; Menk, Ralf Hendrik; Picciotto, Antonino; Piemonte, Claudio; Rachevski, Alexandre; Rashevskaya, Irina; Stolfa, Andrea; Vacchi, Andrea; Zampa, Gianluigi; Zampa, Nicola; Zorzi, Nicola

    2016-04-01

    The last decades have witnessed substantial efforts in the development of several detector technologies for X-ray fluorescence (XRF) applications. In spite of the increasing trend towards performing, cost-effective and reliable XRF systems, detectors for soft X-ray spectroscopy still remain a challenge, requiring further study, engineering and customization in order to yield effective and efficient systems. In this paper we report on the development, first characterization and tests of a novel multielement detector system based on low leakage current silicon drift detectors (SDD) coupled to ultra low noise custom CMOS preamplifiers for synchrotron-based low energy XRF. This new system exhibits the potential for improving the count rate by at least an order of magnitude resulting in ten-fold shorter dwell time at an energy resolution similar to that of single element silicon drift detectors.

  15. A new detector system for low energy X-ray fluorescence coupled with soft X-ray microscopy: First tests and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Gianoncelli, Alessandra, E-mail: alessandra.gianoncelli@elettra.eu [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Bufon, Jernej [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); University of Trieste, Piazzale Europa 1, Trieste 34127 (Italy); Ahangarianabhari, Mahdi [Politecnico di Milano, Via Anzani 42, Como 22100 (Italy); INFN Milano, Via Celoria 16, Milano 20133 (Italy); Altissimo, Matteo [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Bellutti, Pierluigi [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Bertuccio, Giuseppe [Politecnico di Milano, Via Anzani 42, Como 22100 (Italy); INFN Milano, Via Celoria 16, Milano 20133 (Italy); Borghes, Roberto [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Carrato, Sergio [University of Trieste, Piazzale Europa 1, Trieste 34127 (Italy); Cautero, Giuseppe [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Fabiani, Sergio [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Giacomini, Gabriele [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Giuressi, Dario [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Kourousias, George [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); Menk, Ralf Hendrik [Elettra-Sincrotrone Trieste S.C.p.A., Strada Statale SS14, km 163.5, Basovizza 34149 (Italy); INFN Trieste, Padriciano 99, Trieste 34149 (Italy); Picciotto, Antonino; Piemonte, Claudio [Fondazione Bruno Kessler, Via Sommarive 18, Trento 38123 (Italy); Rachevski, Alexandre [INFN Trieste, Padriciano 99, Trieste 34149 (Italy); and others

    2016-04-21

    The last decades have witnessed substantial efforts in the development of several detector technologies for X-ray fluorescence (XRF) applications. In spite of the increasing trend towards performing, cost-effective and reliable XRF systems, detectors for soft X-ray spectroscopy still remain a challenge, requiring further study, engineering and customization in order to yield effective and efficient systems. In this paper we report on the development, first characterization and tests of a novel multielement detector system based on low leakage current silicon drift detectors (SDD) coupled to ultra low noise custom CMOS preamplifiers for synchrotron-based low energy XRF. This new system exhibits the potential for improving the count rate by at least an order of magnitude resulting in ten-fold shorter dwell time at an energy resolution similar to that of single element silicon drift detectors.

  16. X-ray and electron microscopy studies on the biodistribution and biomodification of iron oxide nanoparticles in Daphnia magna.

    Science.gov (United States)

    Kwon, Dongwook; Nho, Hyun Woo; Yoon, Tae Hyun

    2014-10-01

    Biodistribution and biomodification of iron oxide (Fe3O4 and α-Fe2O3) nanoparticles (NPs) in a well-known toxicity test organism, Daphnia magna (D. magna), were investigated using transmission electron microscopy (TEM) and scanning transmission X-ray microscopy (STXM). In addition to the morphological changes in the gut tissues of D. magna, biodistribution and biomodification of iron oxide NPs in the digestive tract of D. magna were also monitored in this study. Upon exposures to both iron oxide NPs, unique morphological changes (e.g., irregular shaped microvilli, epithelial cell protrusion, and dilatation of cytoplasmic inclusion) in the gut tissues of D. magna were observed along with bacterial colonization of the gut lumen. However, despite their heavy accumulations in the digesitive tract, TEM and STXM images confirmed us that both Fe3O4 and α-Fe2O3 NPs were not penetrating into the gut tissues of D. magna. Moreover, for the Fe3O4 NPs in direct contact with the gut microvilli of D. magna, slight but significant spectral changes were observed in their Fe L-edge X-ray absorption near edge structure (XANES) spectra, which indicated that there were biomodifications of Fe3O4 NPs, probably involving oxidative dissolution of Fe3O4 NPs followed by rapid precipitation of ferric oxide or hydroxide. However, no significant changes were observed in the Fe L-edge XANES spectra of the α-Fe2O3 NPs present in the gut lumen of D. magna. These X-ray and electron microscopic observations confirmed us that, despite similarities in core sizes and chemical compositions, NPs with different crystalline phase and dissolution rates can interact quite differently with their local environment, may result in different biodistribution and cause completely dissimilar toxicities.

  17. Three-dimensional foam flow resolved by fast X-ray tomographic microscopy

    CERN Document Server

    Raufaste, Christophe; Mader, Kevin; Santucci, Stéphane; Mokso, Rajmund

    2015-01-01

    Thanks to ultra fast and high resolution X-ray tomography, we managed to capture the evolution of the local structure of the bubble network of a 3D foam flowing around a sphere. As for the 2D foam flow around a circular obstacle, we observed an axisymmetric velocity field with a recirculation zone, and indications of a negative wake downstream the obstacle. The bubble deformations, quantified by a shape tensor, are smaller than in 2D, due to a purely 3D feature: the azimuthal bubble shape variation. Moreover, we were able to detect plastic rearrangements, characterized by the neighbor-swapping of four bubbles. Their spatial structure suggest that rearrangements are triggered when films faces get smaller than a characteristic area.

  18. In situ azimuthal rotation device for linear dichroism measurements in scanning transmission x-ray microscopy

    Science.gov (United States)

    Hernández-Cruz, D.; Hitchcock, A. P.; Tyliszczak, T.; Rousseau, M.-E.; Pézolet, M.

    2007-03-01

    A novel miniature rotation device used in conjunction with a scanning transmission x-ray microscope is described. It provides convenient in situ sample rotation to enable measurements of linear dichroism at high spatial resolution. The design, fabrication, and mechanical characterization are presented. This device has been used to generate quantitative maps of the spatial distribution of the orientation of proteins in several different spider and silkworm silks. Specifically, quantitative maps of the dichroic signal at the C 1s→π*amide transition in longitudinal sections of the silk fibers give information about the spatial orientation, degree of alignment, and spatial distribution of protein peptide bonds. A new approach for analyzing the dichroic signal to extract orientation distributions, in addition to magnitudes of aligned components, is presented and illustrated with results from Nephila clavipes dragline spider silk measured using the in situ rotation device.

  19. Quantitative studies of the nucleation of recrystallization in metals utilizing microscopy and X-ray diffraction

    DEFF Research Database (Denmark)

    Larsen, Axel Wright

    is proven to be a good way of determining microstructural parameters, which are important when studying recrystallization dynamics. The nucleation of recrystallizationat triple junctions has been studied by 3 dimensional X-ray diffraction (3DXRD), allowing for the first time the deformed and recrystallized......This thesis covers three main results obtained during the project: A reliable method of performing serial sectioning on metal samples utilizing a Logitech polishing machine has been developed. Serial sectioning has been performed on metal samples in 1 µmsteps utilizing mechanical polishing......, and in 2 µm steps when electrochemical polishing was needed. A method by which reliable EBSP line scans may be performed by scanning three parallel lines has been developed. This method allows lines of the order of 1cm in length to be characterized with a 1 µm or better spatial resolution. The method...

  20. Investigation of mineral distribution in bone by synchrotron X-ray fluorescence microscopy after tibolone therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lima, I. [Rio de Janeiro State Univ., Nova Friburgo, RJ (Brazil). Dept. of Mechanical Engineering and Energy; Federal Univ. of Rio de Janeiro, RJ (Brazil). Nuclear Instrumentation Lab. - COPPE; Carvalho, A.C.B.; Henriques, H.N.; Guzman-Silva, M.A. [Fluminense Federal Univ., Niteroi, RJ (Brazil). Lab. of Experimental Pathology; Sales, E.; Lopes, R.T. [Federal Univ. of Rio de Janeiro, RJ (Brazil). Nuclear Instrumentation Lab. - COPPE; Granjeiro, J.M. [Fluminense Federal Univ., Niteroi, RJ (Brazil). Dept. of Cellular and Molecular Biology

    2011-07-01

    Tibolone is a synthetic steroid with estrogenic, androgenic, and progestagenic properties used for the prevention of postmenopausal osteoporosis and treatment of climacteric symptoms. Tibolone shows almost no action on breast and endometrium, which are target-organs for estrogens and progesterone activity. The aim of this work was to investigate the spatial distribution of calcium and zinc minerals in the femoral head of ovariectomized rat in order to evaluate the effects of the long-term administration of tibolone. For that purpose X-ray microfluorescence was used with synchrotron radiation imaging technique which was performed at Brazilian Light Synchrotron Laboratory, Campinas, SP. Minerals were not homogeneously distributed in trabecular bone areas; a higher concentration of calcium in the trabecular regions at femoral heads was found in ovariectomized and tibolone-treated rats compared to ovariectomized and control groups. (orig.)

  1. Large area quantitative X-ray mapping of (U,Pu)O 2 nuclear fuel pellets using wavelength dispersive electron probe microanalysis

    Science.gov (United States)

    Brémier, S.; Haas, D.; Somers, J.; Walker, C. T.

    2003-04-01

    The work presented is an example of how large area compositional mapping (≥1 mm 2) can be used to provide quantitative information on element distribution and specimen homogeneity. High-resolution was accomplished by producing a collage of X-ray maps acquired using classical conditions; magnification ×400, spatial resolution 256×256 pixels. The individual images, each measuring roughly 250×250 μm, were converted to quantitative maps using the HIMAX® software package and the XMAS® matrix correction from SAMx. The quantitative gray-level large area X-ray picture was pieced together using the 'Multiple Image Alignment' function of the ANALYSIS® image processing software. This software was also used to convert the gray-level pictures to false color images. The specimens investigated were transverse sections of MOX fuel pellets. Results are presented for the distribution of Pu by area fraction and cumulative area fraction, the size distribution of regions of high Pu concentration and average separation of these regions.

  2. Multi-scale 3D investigations of a commercial 18650 Li-ion battery with correlative electron- and X-ray microscopy

    Science.gov (United States)

    Gelb, Jeff; Finegan, Donal P.; Brett, Dan J. L.; Shearing, Paul R.

    2017-07-01

    In the present study, a commercial 18650 Li-ion cylindrical cell is investigated with non-destructive 3D X-ray microscopy across a range of length scales, beginning with a survey of the entire cell and non-destructively enlarging a smaller section. Active materials are extracted from a disassembled cell and imaging performed using a combination of sub-micron X-ray microscopy and 2D scanning-electron microscopy, which point toward the need for multi-scale analysis in order to accurately characterize the cell. Furthermore, a small section is physically isolated for 3D nano-scale X-ray microscopy, which provides a measurement of porosity and enables the effective diffusivity and 3-dimensional tortuosities to be calculated via computer simulation. Finally, the 3D X-ray microscopy data is loaded into a correlative microscopy environment, where a representative sub-surface region is identified and, subsequently, analyzed using electron microscopy and energy-dispersive X-ray spectroscopy. The results of this study elucidate the microstructural characteristics and potential degradation mechanisms of a commercial NCA battery and, further, establish a technique for extracting the Bruggeman exponent for a real-world microstructure using correlative microscopy.

  3. Fluorescence imaging of reactive oxygen species by confocal laser scanning microscopy for track analysis of synchrotron X-ray photoelectric nanoradiator dose: X-ray pump-optical probe.

    Science.gov (United States)

    Jeon, Jae Kun; Han, Sung Mi; Kim, Jong Ki

    2016-09-01

    penetration by nanoradiators. In conclusion, the combined use of a synchrotron X-ray microbeam-irradiated three-dimensional ROS gel and confocal laser scanning fluorescence microscopy provides a simple dosimetry method for track analysis of X-ray photoelectric nanoradiator radiation, suggesting extensive cellular damage with dose-enhancement beyond a single cell containing IONs.

  4. Raman microscopy and x-ray fluorescence analysis of pigments on medieval and Renaissance Italian manuscript cuttings.

    Science.gov (United States)

    Burgio, Lucia; Clark, Robin J H; Hark, Richard R

    2010-03-30

    Italian medieval and Renaissance manuscript cuttings and miniatures from the Victoria and Albert Museum were analyzed by Raman microscopy to compile a database of pigments used in different periods and different Italian regions. The palette identified in most manuscripts and cuttings was found to include lead white, gypsum, azurite, lazurite, indigo, malachite, vermilion, red lead, lead tin yellow (I), goethite, carbon, and iron gall ink. A few of the miniatures, such as the historiated capital "M" painted by Gerolamo da Cremona and the Petrarca manuscript by Bartolomeo Sanvito, are of exceptional quality and were analyzed extensively; some contained unusual materials. The widespread usage of iron oxides such as goethite and hematite as minor components of mixtures with azurite is particularly notable. The use of a needle-shaped form of iron gall ink as a pigment rather than a writing material was established by both Raman microscopy and x-ray fluorescence spectroscopy for the Madonna and Child by Franco de' Russi.

  5. Domain wall velocity measurement in permalloy nanowires with X-ray magnetic circular dichroism imaging and single shot Kerr microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Moore, T.A., E-mail: t.a.moore@physics.or [Fachbereich Physik, Universitaet Konstanz, Universitaetsstrasse 10, 78457 Konstanz (Germany); Klaeui, M.; Heyne, L.; Moehrke, P. [Fachbereich Physik, Universitaet Konstanz, Universitaetsstrasse 10, 78457 Konstanz (Germany); Backes, D.; Rhensius, J. [Fachbereich Physik, Universitaet Konstanz, Universitaetsstrasse 10, 78457 Konstanz (Germany); Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Ruediger, U. [Fachbereich Physik, Universitaet Konstanz, Universitaetsstrasse 10, 78457 Konstanz (Germany); Heyderman, L.J. [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Mentes, T.O.; Nino, M.A.; Locatelli, A. [Sincrotrone Trieste, 34012 Basovizza-Trieste (Italy); Potenza, A.; Marchetto, H.; Cavill, S.; Dhesi, S.S. [Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE (United Kingdom)

    2010-05-15

    Domain walls (DWs) propagated along nanoscale magnetic wires by current or field pulses could potentially be used for data storage or logic applications, but the understanding of the DW dynamics, particularly under the influence of spin-polarized current, is incomplete. Measuring the velocity can give insights into the physics of the DW motion. Here we demonstrate DW velocity measurements in permalloy (Ni{sub 80}Fe{sub 20}) nanowires (1500 nm width and 20 nm thickness) using the techniques of X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) to image the magnetic contrast in the nanowires, and single shot Kerr microscopy, which allows for dynamic measurements. The magnetic imaging yields the average velocity as well as information on the DW spin structure, whereas the single shot method highlights the stochastic nature of the DW motion.

  6. A histochemical and X-ray microanalysis study of calcium changes in insect flight muscle degeneration in Solenopsis, the queen fire ant

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.G.; Davis, W.L.; Vinson, S.B.

    1982-04-01

    Potassium pyroantimonate histochemistry, coupled with ethyleneglycoltetraacetic acid (EGTA)-chelation and X-ray microprobe analysis, was employed to localize intracellular calcium binding sites in the normal and degenerating flight musculature in queens of Solenopsis, the fire ant. In normal animals, calcium distribution was light to moderate within myofibrils and mitochondria. In the early contracture stages of the insemination-induced degeneration, both myofilament and mitochondrial calcium loading was markedly increased. In the terminal stages of myofibril breakdown, only Z-lines (isolated or in clusters) with an associated filamentous residue persisted. These complexes were also intensely calcium positive. This study further documents the presence of increased sarcoplasmic calcium during muscle necrosis. Surface membrane defects, mitochondrial calcium overload, and calcium-activated proteases may all be involved in this ''normal'' breakdown process.

  7. New insights into globoids of protein storage vacuoles in wheat aleurone using synchrotron soft X-ray microscopy.

    Science.gov (United States)

    Regvar, Marjana; Eichert, Diane; Kaulich, Burkhard; Gianoncelli, Alessandra; Pongrac, Paula; Vogel-Mikus, Katarina; Kreft, Ivan

    2011-07-01

    Mature developed seeds are physiologically and biochemically committed to store nutrients, principally as starch, protein, oils, and minerals. The composition and distribution of elements inside the aleurone cell layer reflect their biogenesis, structural characteristics, and physiological functions. It is therefore of primary importance to understand the mechanisms underlying metal ion accumulation, distribution, storage, and bioavailability in aleurone subcellular organelles for seed fortification purposes. Synchrotron radiation soft X-ray full-field imaging mode (FFIM) and low-energy X-ray fluorescence (LEXRF) spectromicroscopy were applied to characterize major structural features and the subcellular distribution of physiologically important elements (Zn, Fe, Na, Mg, Al, Si, and P). These direct imaging methods reveal the accumulation patterns between the apoplast and symplast, and highlight the importance of globoids with phytic acid mineral salts and walls as preferential storage structures. C, N, and O chemical topographies are directly linked to the structural backbone of plant substructures. Zn, Fe, Na, Mg, Al, and P were linked to globoid structures within protein storage vacuoles with variable levels of co-localization. Si distribution was atypical, being contained in the aleurone apoplast and symplast, supporting a physiological role for Si in addition to its structural function. These results reveal that the immobilization of metals within the observed endomembrane structures presents a structural and functional barrier and affects bioavailability. The combination of high spatial and chemical X-ray microscopy techniques highlights how in situ analysis can yield new insights into the complexity of the wheat aleurone layer, whose precise biochemical composition, morphology, and structural characteristics are still not unequivocally resolved.

  8. Scanning Transmission X-ray Microscopy with X-ray Fluorescence Detection at the XUV Beamline P04, PETRA III, DESY

    Science.gov (United States)

    Andrianov, K.; Lühl, L.; Nisius, T.; Haidl, A.; Gnewkow, R.; Lötgering, L.; Dierks, H.; Kanngießer, B.; Wilhein, T.

    2017-06-01

    The presented scanning transmission x-ray microscope (STXM), build on top of our existing modular platform (FlexIX) for high resolution imaging experiments, allows versatile investigations of different samples. The FlexIX endstation allows to switch between a Full Field and a STXM mode. For the STXM mode we use a spatialy resolved detector together with an energy dispersive detector, this allows to investigate the morphology and the chemical or elemental distribution of the sample simultaneous. The combination of the nanoscopy endstation and the XUV beamline P04 results in a powerful tool for investigations of life science samples.

  9. Combined small angle X-ray solution scattering with atomic force microscopy for characterizing radiation damage on biological macromolecules.

    Science.gov (United States)

    Costa, Luca; Andriatis, Alexander; Brennich, Martha; Teulon, Jean-Marie; Chen, Shu-Wen W; Pellequer, Jean-Luc; Round, Adam

    2016-10-27

    Synchrotron radiation facilities are pillars of modern structural biology. Small-Angle X-ray scattering performed at synchrotron sources is often used to characterize the shape of biological macromolecules. A major challenge with high-energy X-ray beam on such macromolecules is the perturbation of sample due to radiation damage. By employing atomic force microscopy, another common technique to determine the shape of biological macromolecules when deposited on flat substrates, we present a protocol to evaluate and characterize consequences of radiation damage. It requires the acquisition of images of irradiated samples at the single molecule level in a timely manner while using minimal amounts of protein. The protocol has been tested on two different molecular systems: a large globular tetremeric enzyme (β-Amylase) and a rod-shape plant virus (tobacco mosaic virus). Radiation damage on the globular enzyme leads to an apparent increase in molecular sizes whereas the effect on the long virus is a breakage into smaller pieces resulting in a decrease of the average long-axis radius. These results show that radiation damage can appear in different forms and strongly support the need to check the effect of radiation damage at synchrotron sources using the presented protocol.

  10. Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5–10 GHz frequency range

    Energy Technology Data Exchange (ETDEWEB)

    Bonetti, Stefano, E-mail: bonetti@slac.stanford.edu; Chen, Zhao [Department of Physics, Stanford University, Stanford, California 94305 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Kukreja, Roopali [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); Spoddig, Detlef; Schöppner, Christian; Meckenstock, Ralf [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); Ollefs, Katharina [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Ney, Andreas [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); Solid State Physics Division, Johannes Kepler University, 4040 Linz (Austria); Pinto, Jude; Houanche, Richard; Frisch, Josef [Linear Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Stöhr, Joachim; Dürr, Hermann A. [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Ohldag, Hendrik [Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

    2015-09-15

    We present a scanning transmission x-ray microscopy setup combined with a novel microwave synchronization scheme for studying high frequency magnetization dynamics at synchrotron light sources. The sensitivity necessary to detect small changes in the magnetization on short time scales and nanometer spatial dimensions is achieved by combining the excitation mechanism with single photon counting electronics that is locked to the synchrotron operation frequency. Our instrument is capable of creating direct images of dynamical phenomena in the 5-10 GHz range, with high spatial resolution. When used together with circularly polarized x-rays, the above capabilities can be combined to study magnetic phenomena at microwave frequencies, such as ferromagnetic resonance (FMR) and spin waves. We demonstrate the capabilities of our technique by presenting phase resolved images of a ∼6 GHz nanoscale spin wave generated by a spin torque oscillator, as well as the uniform ferromagnetic precession with ∼0.1° amplitude at ∼9 GHz in a micrometer-sized cobalt strip.

  11. Germanium Collimating micro-Channel Arrays For High Resolution, High Energy Confocal X-ray Fluorescence Microscopy

    CERN Document Server

    Agyeman-Budu, David N; Coulthard, Ian; Gordon, Robert; Hallin, Emil; Woll, Arthur R

    2016-01-01

    Confocal x-ray fluorescence microscopy (CXRF) allows direct detection of x-ray fluorescence from a micron-scale 3D volume of an extended, unthinned sample. We have previously demonstrated the use of a novel collection optic, fabricated from silicon, that improves the spatial resolution of this approach by an order of magnitude over CXRF using polycapillaries. The optic, called a collimating channel array (CCA), consists of micron-scale, lithographically-fabricated arrays of collimating channels, all directed towards a single source position. Due to the limited absorbing power of silicon, the useful energy range of these optics was limited to fluorescence emission below about 10 keV. Here, we report fabrication of CCAs from germanium substrates, and demonstrate their practical use for CXRF up to 20 keV. Specifically we demonstrate a nearly energy-independent critical spatial resolution $d_R$ of 2.1$\\pm$0.17 \\um from 2-20 keV, as well as excellent background reduction compared to silicon-based CCAs throughout t...

  12. Mesoscopic structural phase progression in photo-excited VO2 revealed by time-resolved x-ray diffraction microscopy

    Science.gov (United States)

    Zhu, Yi; Cai, Zhonghou; Chen, Pice; Zhang, Qingteng; Highland, Matthew J.; Jung, Il Woong; Walko, Donald A.; Dufresne, Eric M.; Jeong, Jaewoo; Samant, Mahesh G.; Parkin, Stuart S. P.; Freeland, John W.; Evans, Paul G.; Wen, Haidan

    2016-02-01

    Dynamical phase separation during a solid-solid phase transition poses a challenge for understanding the fundamental processes in correlated materials. Critical information underlying a phase transition, such as localized phase competition, is difficult to reveal by measurements that are spatially averaged over many phase separated regions. The ability to simultaneously track the spatial and temporal evolution of such systems is essential to understanding mesoscopic processes during a phase transition. Using state-of-the-art time-resolved hard x-ray diffraction microscopy, we directly visualize the structural phase progression in a VO2 film upon photoexcitation. Following a homogenous in-plane optical excitation, the phase transformation is initiated at discrete sites and completed by the growth of one lattice structure into the other, instead of a simultaneous isotropic lattice symmetry change. The time-dependent x-ray diffraction spatial maps show that the in-plane phase progression in laser-superheated VO2 is via a displacive lattice transformation as a result of relaxation from an excited monoclinic phase into a rutile phase. The speed of the phase front progression is quantitatively measured, and is faster than the process driven by in-plane thermal diffusion but slower than the sound speed in VO2. The direct visualization of localized structural changes in the time domain opens a new avenue to study mesoscopic processes in driven systems.

  13. The architecture of amyloid-like peptide fibrils revealed by X-ray scattering, diffraction and electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Langkilde, Annette E., E-mail: annette.langkilde@sund.ku.dk [University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen (Denmark); Morris, Kyle L.; Serpell, Louise C. [University of Sussex, Falmer, Brighton (United Kingdom); Svergun, Dmitri I. [European Molecular Biology Laboratory, Hamburg Outstation, 22607 Hamburg (Germany); Vestergaard, Bente [University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen (Denmark)

    2015-04-01

    The aggregation process and the fibril state of an amyloidogenic peptide suggest monomer addition to be the prevailing mechanism of elongation and a model of the peptide packing in the fibrils has been obtained. Structural analysis of protein fibrillation is inherently challenging. Given the crucial role of fibrils in amyloid diseases, method advancement is urgently needed. A hybrid modelling approach is presented enabling detailed analysis of a highly ordered and hierarchically organized fibril of the GNNQQNY peptide fragment of a yeast prion protein. Data from small-angle X-ray solution scattering, fibre diffraction and electron microscopy are combined with existing high-resolution X-ray crystallographic structures to investigate the fibrillation process and the hierarchical fibril structure of the peptide fragment. The elongation of these fibrils proceeds without the accumulation of any detectable amount of intermediate oligomeric species, as is otherwise reported for, for example, glucagon, insulin and α-synuclein. Ribbons constituted of linearly arranged protofilaments are formed. An additional hierarchical layer is generated via the pairing of ribbons during fibril maturation. Based on the complementary data, a quasi-atomic resolution model of the protofilament peptide arrangement is suggested. The peptide structure appears in a β-sheet arrangement reminiscent of the β-zipper structures evident from high-resolution crystal structures, with specific differences in the relative peptide orientation. The complexity of protein fibrillation and structure emphasizes the need to use multiple complementary methods.

  14. Electron Microscopy and Analytical X-ray Characterization of Compositional and Nanoscale Structural Changes in Fossil Bone

    Science.gov (United States)

    Boatman, Elizabeth Marie

    The nanoscale structure of compact bone contains several features that are direct indicators of bulk tissue mechanical properties. Fossil bone tissues represent unique opportunities to understand the compact bone structure/property relationships from a deep time perspective, offering a possible array of new insights into bone diseases, biomimicry of composite materials, and basic knowledge of bioapatite composition and nanoscale bone structure. To date, most work with fossil bone has employed microscale techniques and has counter-indicated the survival of bioapatite and other nanoscale structural features. The obvious disconnect between the use of microscale techniques and the discernment of nanoscale structure has prompted this work. The goal of this study was to characterize the nanoscale constituents of fossil compact bone by applying a suite of diffraction, microscopy, and spectrometry techniques, representing the highest levels of spatial and energy resolution available today, and capable of complementary structural and compositional characterization from the micro- to the nanoscale. Fossil dinosaur and crocodile long bone specimens, as well as modern ratite and crocodile femurs, were acquired from the UC Museum of Paleontology. Preserved physiological features of significance were documented with scanning electron microscopy back-scattered imaging. Electron microprobe wavelength-dispersive X-ray spectroscopy (WDS) revealed fossil bone compositions enriched in fluorine with a complementary loss of oxygen. X-ray diffraction analyses demonstrated that all specimens were composed of apatite. Transmission electron microscopy (TEM) imaging revealed preserved nanocrystallinity in the fossil bones and electron diffraction studies further identified these nanocrystallites as apatite. Tomographic analyses of nanoscale elements imaged by TEM and small angle X-ray scattering were performed, with the results of each analysis further indicating that nanoscale structure is

  15. Aluminum-phosphate binder formation in zeolites as probed with X-ray absorption microscopy.

    Science.gov (United States)

    van der Bij, Hendrik E; Cicmil, Dimitrije; Wang, Jian; Meirer, Florian; de Groot, Frank M F; Weckhuysen, Bert M

    2014-12-24

    In this work, three industrially relevant zeolites with framework topologies of MOR, FAU and FER have been explored on their ability to form an AlPO4 phase by reaction of a phosphate precursor with expelled framework aluminum. A detailed study was performed on zeolite H-mordenite, using in situ STXM and soft X-ray absorption tomography, complemented with (27)Al and (31)P magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, XRD, FT-IR spectroscopy, and N2 physisorption. Extraframework aluminum was extracted from steam-dealuminated H-mordenite and shown to dominantly consist of amorphous AlO(OH). It was found that phosphoric acid readily reacts with the AlO(OH) phase in dealuminated H-mordenite and forms an extraframework amorphous AlPO4 phase. It was found that while AlPO4 crystallizes outside of the zeolitic channel system forming AlPO4 islands, AlPO4 that remains inside tends to stay more amorphous. In the case of ultrastable zeolite Y the FAU framework collapsed during phosphatation, due to extraction of framework aluminum from the lattice. However, using milder phosphatation conditions an extraframework AlPO4 α-cristobalite/tridymite phase could also be produced within the FAU framework. Finally, in steamed zeolite ferrierite with FER topology the extraframework aluminum species were trapped and therefore not accessible for phosphoric acid; hence, no AlPO4 phase could be formed within the structure. Therefore, the parameters to be taken into account in AlPO4 synthesis are the framework Si/Al ratio, stability of framework aluminum, pore dimensionality and accessibility of extraframework aluminum species.

  16. Proton induced X-ray emission and electron microscopy analysis of induced mutants of sorghum

    CSIR Research Space (South Africa)

    Mbambo, Z

    2014-01-01

    Full Text Available of elements in preferential accumulation tissues and entire changes in cellular localization. Transmission and scanning electron microscopy of the mutants resolved changes in size, shape, ultra-structure and packed cell volumes of protein- and starch bodies...

  17. Repeatability and reproducibility of intracellular molar concentration assessed by synchrotron-based x-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Merolle, L., E-mail: lucia.merolle@elettra.eu; Gianoncelli, A. [Elettra - Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy); Malucelli, E., E-mail: emil.malucelli@unibo.it; Cappadone, C.; Farruggia, G.; Sargenti, A.; Procopio, A. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); Fratini, M. [Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Piazza del Viminale 1, 00184 Roma Italy (Italy); Department of Science, Roma Tre University, Via della Vasca Navale 84, I-00146 Rome (Italy); Notargiacomo, A. [Institute for Photonics and Nanotechnology, Consiglio Nazionale delle Richerche, 00156 Rome (Italy); Lombardo, M. [Department of Chemistry “G. Ciamician”, University of Bologna, Bologna 40126 (Italy); Lagomarsino, S. [Institute of Chemical-Physical Processes, Sapienza University of Rome, 00185 Rome (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy); Iotti, S. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy)

    2016-01-28

    Elemental analysis of biological sample can give information about content and distribution of elements essential for human life or trace elements whose absence is the cause of abnormal biological function or development. However, biological systems contain an ensemble of cells with heterogeneous chemistry and elemental content; therefore, accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. Powerful methods in molecular biology are abundant, among them X-Ray microscopy based on synchrotron light source has gaining increasing attention thanks to its extremely sensitivity. However, reproducibility and repeatability of these measurements is one of the major obstacles in achieving a statistical significance in single cells population analysis. In this study, we compared the elemental content of human colon adenocarcinoma cells obtained by three distinct accesses to synchrotron radiation light.

  18. Visualizing Cell Architecture and Molecular Location Using Soft X-Ray Tomography and Correlated Cryo-Light Microscopy

    Science.gov (United States)

    McDermott, Gerry; Le Gros, Mark A.; Larabell, Carolyn A.

    2012-05-01

    Living cells are structured to create a range of microenvironments that support specific chemical reactions and processes. Understanding how cells function therefore requires detailed knowledge of both the subcellular architecture and the location of specific molecules within this framework. Here we review the development of two correlated cellular imaging techniques that fulfill this need. Cells are first imaged using cryogenic fluorescence microscopy to determine the location of molecules of interest that have been labeled with fluorescent tags. The same specimen is then imaged using soft X-ray tomography to generate a high-contrast, 3D reconstruction of the cells. Data from the two modalities are then combined to produce a composite, information-rich view of the cell. This correlated imaging approach can be applied across the spectrum of problems encountered in cell biology, from basic research to biotechnological and biomedical applications such as the optimization of biofuels and the development of new pharmaceuticals.

  19. Combined use of atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry for cell surface analysis.

    Science.gov (United States)

    Dague, Etienne; Delcorte, Arnaud; Latgé, Jean-Paul; Dufrêne, Yves F

    2008-04-01

    Understanding the surface properties of microbial cells is a major challenge of current microbiological research and a key to efficiently exploit them in biotechnology. Here, we used three advanced surface analysis techniques with different sensitivity, probing depth, and lateral resolution, that is, in situ atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry, to gain insight into the surface properties of the conidia of the human fungal pathogen Aspergillus fumigatus. We show that the native ultrastructure, surface protein and polysaccharide concentrations, and amino acid composition of three mutants affected in hydrophobin production are markedly different from those of the wild-type, thereby providing novel insight into the cell wall architecture of A. fumigatus. The results demonstrate the power of using multiple complementary techniques for probing microbial cell surfaces.

  20. Repeatability and reproducibility of intracellular molar concentration assessed by synchrotron-based x-ray fluorescence microscopy

    Science.gov (United States)

    Merolle, L.; Malucelli, E.; Fratini, M.; Gianoncelli, A.; Notargiacomo, A.; Cappadone, C.; Farruggia, G.; Sargenti, A.; Procopio, A.; Lombardo, M.; Lagomarsino, S.; Iotti, S.

    2016-01-01

    Elemental analysis of biological sample can give information about content and distribution of elements essential for human life or trace elements whose absence is the cause of abnormal biological function or development. However, biological systems contain an ensemble of cells with heterogeneous chemistry and elemental content; therefore, accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. Powerful methods in molecular biology are abundant, among them X-Ray microscopy based on synchrotron light source has gaining increasing attention thanks to its extremely sensitivity. However, reproducibility and repeatability of these measurements is one of the major obstacles in achieving a statistical significance in single cells population analysis. In this study, we compared the elemental content of human colon adenocarcinoma cells obtained by three distinct accesses to synchrotron radiation light.

  1. Nail Damage (Severe Onychodystrophy) Induced by Acrylate Glue: Scanning Electron Microscopy and Energy Dispersive X-Ray Investigations

    Science.gov (United States)

    Pinteala, Tudor; Chiriac, Anca Eduard; Rosca, Irina; Larese Filon, Francesca; Pinteala, Mariana; Chiriac, Anca; Podoleanu, Cristian; Stolnicu, Simona; Coros, Marius Florin; Coroaba, Adina

    2017-01-01

    Background Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques have been used in various fields of medical research, including different pathologies of the nails; however, no studies have focused on obtaining high-resolution microscopic images and elemental analysis of disorders caused by synthetic nails and acrylic adhesives. Methods Damaged/injured fingernails caused by the use of acrylate glue and synthetic nails were investigated using SEM and EDX methods. Results SEM and EDX proved that synthetic nails, acrylic glue, and nails damaged by contact with acrylate glue have a different morphology and different composition compared to healthy human nails. Conclusions SEM and EDX analysis can give useful information about the aspects of topography (surface sample), morphology (shape and size), hardness or reflectivity, and the elemental composition of nails. PMID:28232921

  2. A median-Gaussian filtering framework for Moiré pattern noise removal from X-ray microscopy image.

    Science.gov (United States)

    Wei, Zhouping; Wang, Jian; Nichol, Helen; Wiebe, Sheldon; Chapman, Dean

    2012-02-01

    Moiré pattern noise in Scanning Transmission X-ray Microscopy (STXM) imaging introduces significant errors in qualitative and quantitative image analysis. Due to the complex origin of the noise, it is difficult to avoid Moiré pattern noise during the image data acquisition stage. In this paper, we introduce a post-processing method for filtering Moiré pattern noise from STXM images. This method includes a semi-automatic detection of the spectral peaks in the Fourier amplitude spectrum by using a local median filter, and elimination of the spectral noise peaks using a Gaussian notch filter. The proposed median-Gaussian filtering framework shows good results for STXM images with the size of power of two, if such parameters as threshold, sizes of the median and Gaussian filters, and size of the low frequency window, have been properly selected.

  3. Stochastic limits in synchronous imaging of sub-micron magnetization dynamics using scanning transmission x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cheng C.; Kaznatcheev K.; Bailey, W.E.

    2012-02-28

    We demonstrate a synchronous (lock-in) technique for imaging thin-film magnetization dynamics using scanning transmission x-ray microscopy (STXM). Gated photon counting synchronized with magnetic field modulation allows image acquisition with differential contrast for high and low magnetization. We have applied this technique to 5 x 12 {micro}m{sup 2} Ni{sub 81}Fe{sub 19} ellipses with well-defined closure domains at remanence. The stochastic nature of the domain wall motion and nucleation is apparent in images recorded during cycling along successive major hysteresis loops. Synchronous imaging shows the clearest enhancement of contrast for small-amplitude domain wall motion, with a less obvious benefit at higher fields/displacements. The technique shows promise for the contrast enhancement of magnetization in dynamics in STXM.

  4. Structure of the Lassa virus nucleoprotein revealed by X-ray crystallography, small-angle X-ray scattering, and electron microscopy.

    Science.gov (United States)

    Brunotte, Linda; Kerber, Romy; Shang, Weifeng; Hauer, Florian; Hass, Meike; Gabriel, Martin; Lelke, Michaela; Busch, Carola; Stark, Holger; Svergun, Dmitri I; Betzel, Christian; Perbandt, Markus; Günther, Stephan

    2011-11-04

    The nucleoprotein (NP) of Lassa virus (LASV) strain AV was expressed in a recombinant baculovirus system. The crystal structure of full-length NP was solved at a resolution of 2.45 Å. The overall fold corresponds to that of NP of LASV strain Josiah (Qi, X., Lan, S., Wang, W., Schelde, L. M., Dong, H., Wallat, G. D., Ly, H., Liang, Y., and Dong, C. (2010) Nature 468, 779-783) with a root mean square deviation of 0.67 Å for all atoms (6.3% difference in primary sequence). As the packing in the crystal offers two different trimer architectures for the biological assembly, the quaternary structure of NP in solution was determined by small-angle x-ray scattering and EM. After classification and averaging of >6000 EM raw images, trimeric centrosymmetric structures were obtained, which correspond in size and shape to one trimer in the crystal structure formed around a crystallographic 3-fold rotation axis (symmetric trimer). The symmetric trimer is also a good model for the small-angle x-ray scattering data and could be well embedded into the ab initio model. The N-terminal domain of NP contains a deep nucleotide-binding cavity that has been proposed to bind cellular cap structures for priming viral mRNA synthesis. All residues implicated in m(7)GpppN binding were exchanged, and the transcription/replication phenotype of the NP mutant was tested using a LASV replicon system. None of the mutants showed a specific defect in mRNA expression; most were globally defective in RNA synthesis. In conclusion, we describe the full-length crystal structure and the quaternary structure in solution of LASV NP. The nucleotide-binding pocket of NP could not be assigned a specific role in viral mRNA synthesis.

  5. Characterisation of mineralisation of bone and cartilage: X-ray diffraction and Ca and Sr K α X-ray fluorescence microscopy

    Science.gov (United States)

    Bradley, D. A.; Muthuvelu, P.; Ellis, R. E.; Green, E. M.; Attenburrow, D.; Barrett, R.; Arkill, K.; Colridge, D. B.; Winlove, C. P.

    2007-10-01

    Bone is a dynamic structure, constantly remodelling in response to changing mechanical and environmental factors. This is particularly evident in the mineral component encrusting the collagenous framework. The mineral is principally in the form of calcium apatite, but calcium can exchange with strontium, both during the cellular processes of mineralisation and resorption and by passive exchange with the deposited crystals. Mineralisation is generally characterized by densitometry, but because of the differences in absorption cross sections of calcium and strontium it can be misleading in studies of composition. In this work we have used X-ray diffraction to identify calcium and strontium apatite and X-ray fluorescence to quantify strontium and calcium distribution. With the beam characteristics available from synchrotron radiation, this has enabled us to obtain microscopic resolution on thin sections of bone and cartilage from the equine metacarpophalangeal joint. Two issues have been investigated; the first is the distribution of mineral in the bone-cartilage interface and within individual trabeculae. In trabecular bone the ratio of strontium to calcium concentration was typically 0.0035 ± 0.0020, and higher by a factor of ∼3 at the periphery than in the centre of a trabeculum (possibly reflecting the more rapid turnover of mineral in the surface layer). In the dense subchondral bone the ratio was similar, approximately doubling in the calcified cartilage. The second objective was to explore the changes in mineralisation associated with development of osteoarthrosis. We analysed lesions showing cartilage thinning and changes in the trabecular organization and density of the underlying bone. At the centre of the lesion the ratio of strontium to calcium was much lower than that in normal tissue, although the calcified cartilage still showed a higher ratio than the underlying bone. In the superficially normal tissue around the lesion the calcified cartilage

  6. Characterisation of mineralisation of bone and cartilage: X-ray diffraction and Ca and Sr K{sub {alpha}} X-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.A. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)], E-mail: d.a.bradley@surrey.ac.uk; Muthuvelu, P.; Ellis, R.E.; Green, E.M.; Attenburrow, D. [Biomedical Physics Group, School of Physics, University of Exeter, Exeter (United Kingdom); Barrett, R. [ESRF, BP 220, F-38043 Grenoble Cedex (France); Arkill, K.; Colridge, D.B.; Winlove, C.P. [Biomedical Physics Group, School of Physics, University of Exeter, Exeter (United Kingdom)

    2007-10-15

    Bone is a dynamic structure, constantly remodelling in response to changing mechanical and environmental factors. This is particularly evident in the mineral component encrusting the collagenous framework. The mineral is principally in the form of calcium apatite, but calcium can exchange with strontium, both during the cellular processes of mineralisation and resorption and by passive exchange with the deposited crystals. Mineralisation is generally characterized by densitometry, but because of the differences in absorption cross sections of calcium and strontium it can be misleading in studies of composition. In this work we have used X-ray diffraction to identify calcium and strontium apatite and X-ray fluorescence to quantify strontium and calcium distribution. With the beam characteristics available from synchrotron radiation, this has enabled us to obtain microscopic resolution on thin sections of bone and cartilage from the equine metacarpophalangeal joint. Two issues have been investigated; the first is the distribution of mineral in the bone-cartilage interface and within individual trabeculae. In trabecular bone the ratio of strontium to calcium concentration was typically 0.0035 {+-} 0.0020, and higher by a factor of {approx}3 at the periphery than in the centre of a trabeculum (possibly reflecting the more rapid turnover of mineral in the surface layer). In the dense subchondral bone the ratio was similar, approximately doubling in the calcified cartilage. The second objective was to explore the changes in mineralisation associated with development of osteoarthrosis. We analysed lesions showing cartilage thinning and changes in the trabecular organization and density of the underlying bone. At the centre of the lesion the ratio of strontium to calcium was much lower than that in normal tissue, although the calcified cartilage still showed a higher ratio than the underlying bone. In the superficially normal tissue around the lesion the calcified

  7. Cryofixation, ultracryomicrotomy, and X-ray microanalysis of enterocytes from chick duodenum: Vitamin-D-induced formation of an apical tubulovesicular system

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.L.; Hagler, H.K.; Jones, R.G.; Farmer, G.R.; Cooper, O.J.; Martin, J.H.; Bridges, G.E.; Goodman, D.B. (Baylor Univ. Medical Center, Dallas, TX (USA))

    1991-02-01

    New methods of tissue preparation were developed to study the morphology and distribution of calcium ions in duodenal enterocytes from normal, rachitic, and vitamin D-replete (either cholecalciferol (CC) or 1,25-dihydroxycholecalciferol (1,25-DHCC) treated) chicks. Frozen hydrated sections were prepared from cryofixed tissues by ultracryomicrotomy at -125 degrees C. Sections were subsequently freeze-dried by increasing the temperature to -100 degrees C. The latter temperature was maintained throughout both the structural and elemental analyses. In cells from normal, rachitic, and vitamin D-treated (CC) animals the brush border from lanthanum-infused tissues was electron dense and calcium-lanthanum positive by x-ray analysis. In the absence of lanthanum, i.e., sucrose-infused duodena, the microvilli were still calcium positive. In the terminal web region of normal and CC-treated enterocytes, numerous, apparently interconnected, tubules and vesicles were seen. Vacuole-like structures were also seen. Such structures were especially prominent in the enterocytes from the vitamin-treated (CC) animals. Except for the vacuoles, the tubules and vesicles were electron dense in the lanthanum-infused duodena, and clear in sucrose-infused tissues. In both instances, the structures were calcium positive. Similar, but even larger structures were seen below the terminal web. Here however, the tubules and vesicles seemed to be organized into multiple complex interconnecting networks, i.e., tubulo-vesicular complexes. Both the tubules and the vesicles seemed to be interconnected via smaller channel-like entities. The extensiveness of this structure was better appreciated in the enterocytes from lanthanum-infused tissues, where it appeared similar in structure and complexity to an en face view of the sarcoplasmic reticulum of skeletal muscle.

  8. Investigation of Measurement Condition for 3-Dimensional Spectroscopy by Scanning Transmission X-ray Microscopy

    Science.gov (United States)

    Ohigashi, T.; Inagaki, Y.; Ito, A.; Shinohara, K.; Kosugi, N.

    2017-06-01

    A sample cell for performing computed tomography (CT) was developed. The 3-dimensional (3D) structure of polystyrene spheres was observed and the fluctuation of reconstructed linear absorption coefficients (LAC) was 9.3%. To improve the quality of data in 3D spectro-microscopy, required measurement condition is discussed.

  9. Component analyses of urinary nanocrystallites of uric acid stone formers by combination of high-resolution transmission electron microscopy, fast Fourier transformation, energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Sun, Xin-Yuan; Xue, Jun-Fa; Xia, Zhi-Yue; Ouyang, Jian-Ming

    2015-06-01

    This study aimed to analyse the components of nanocrystallites in urines of patients with uric acid (UA) stones. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy (HRTEM), fast Fourier transformation (FFT) of HRTEM, and energy dispersive X-ray spectroscopy (EDS) were performed to analyse the components of these nanocrystallites. XRD and FFT showed that the main component of urinary nanocrystallites was UA, which contains a small amount of calcium oxalate monohydrate and phosphates. EDS showed the characteristic absorption peaks of C, O, Ca and P. The formation of UA stones was closely related to a large number of UA nanocrystallites in urine. A combination of HRTEM, FFT, EDS and XRD analyses could be performed accurately to analyse the components of urinary nanocrystallites.

  10. In situ characterization of aluminum-containing mineral-microorganism aqueous suspensions using scanning transmission X-ray microscopy.

    Science.gov (United States)

    Yoon, Tae Hyun; Johnson, Stephen B; Benzerara, Karim; Doyle, Colin S; Tyliszczak, Tolek; Shuh, David K; Brown, Gordon E

    2004-11-23

    In situ characterization of colloidal particles under hydrous conditions is one of the key requirements for understanding their state of aggregation and impact on the transport of pollutants in aqueous environments. Scanning transmission X-ray microscopy (STXM) is one of the few techniques that can satisfy this need by providing element- and chemical-state-specific 2-D maps at a spatial resolution better than 50 nm using soft X-rays from synchrotron radiation wiggler or undulator sources tuned to the absorption edges of different elements. X-ray absorption near-edge structure (XANES) spectra can also be collected simultaneously at a similar spatial resolution and can provide phase identification in many cases. In this study, we report STXM images and XANES spectroscopy measurements at or above the Al K-edge (E = 1559.6 eV) of various Al-containing minerals and synthetic oxides [alpha-Al2O3 (corundum), gamma-Al2O3, gamma-AlOOH (boehmite), alpha-Al(OH)3 (bayerite), KAl2(AlSi3O10)(OH)2 (muscovite), (Al,Mg)8(Si4O10)4(OH)8.nH2O (montmorillonite), and Mg6Al2(OH)16CO3.4H2O (hydrotalcite)] and demonstrate the capability of this spectromicroscopic tool to identify different Al-containing mineral colloids in multiphase mixtures in aqueous solution. We also demonstrate that STXM imaging at or above the C K-edge (E = 284.2 eV) and Al K-edge can provide unique information on the interactions between bacteria and Al-containing nanoparticles in aqueous suspensions. STXM images of a mixture of Caulobacter crescentus and montmorillonite and corundum particles just above the C and Al K-edges show that the mineral particles and bacteria are closely associated in aggregates, which is likely due to the binding of bacteria to clay and corundum particles by extracellular polysaccharides.

  11. Study of radiation effects on the cell structure and evaluation of the dose delivered by x-ray and {alpha}-particles microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kosior, Ewelina; Cloetens, Peter [European Synchrotron Radiation Facility, F-38000 Grenoble (France); Deves, Guillaume; Ortega, Richard [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Bohic, Sylvain [European Synchrotron Radiation Facility, 38000 Grenoble (France); INSERM U-836 (Team 6: Synchrotron Radiation and Medical Research), Grenoble Institut of Neuroscience, F-38000 Grenoble (France)

    2012-12-24

    Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to study radiation effects on cells. Experiments were performed on freeze-dried cells at the nano-imaging station ID22NI of the European synchrotron radiation facility. Quantitative phase contrast imaging provides maps of the projected mass and is used to evaluate the structural changes due to irradiation during X-ray fluorescence experiments. Complementary to phase contrast imaging, scanning transmission ion microscopy is performed and doses of all the experiments are compared. We demonstrate the sensitivity of the proposed approach to study radiation-induced damage at the sub-cellular level.

  12. Ordering in bio-inorganic hybrid nanomaterials probed by in situ scanning transmission X-ray microscopy

    Science.gov (United States)

    Lee, Jonathan R. I.; Bagge-Hansen, Michael; Tunuguntla, Ramya; Kim, Kyunghoon; Bangar, Mangesh; Willey, Trevor M.; Tran, Ich C.; Kilcoyne, David A.; Noy, Aleksandr; van Buuren, Tony

    2015-05-01

    Phospholipid bilayer coated Si nanowires are one-dimensional (1D) composites that provide versatile bio-nanoelectronic functionality via incorporation of a wide variety of biomolecules into the phospholipid matrix. The physiochemical behaviour of the phospholipid bilayer is strongly dependent on its structure and, as a consequence, substantial modelling and experimental efforts have been directed at the structural characterization of supported bilayers and unsupported phospholipid vesicles; nonetheless, the experimental studies conducted to date have exclusively involved volume-averaged techniques, which do not allow for the assignment of spatially resolved structural variations that could critically impact the performance of the 1D phospholipid-Si NW composites. In this manuscript, we use scanning transmission X-ray microscopy (STXM) to probe bond orientation and bilayer thickness as a function of position with a spatial resolution of ~30 nm for Δ9-cis 1,2-dioleoyl-sn-glycero-3-phosphocholine layers prepared Si NWs. When coupled with small angle X-ray scattering measurements, the STXM data reveal structural motifs of the Si NWs that give rise to multi-bilayer formation and enable assignment of the orientation of specific bonds known to affect the order and rigidity of phospholipid bilayers.Phospholipid bilayer coated Si nanowires are one-dimensional (1D) composites that provide versatile bio-nanoelectronic functionality via incorporation of a wide variety of biomolecules into the phospholipid matrix. The physiochemical behaviour of the phospholipid bilayer is strongly dependent on its structure and, as a consequence, substantial modelling and experimental efforts have been directed at the structural characterization of supported bilayers and unsupported phospholipid vesicles; nonetheless, the experimental studies conducted to date have exclusively involved volume-averaged techniques, which do not allow for the assignment of spatially resolved structural

  13. Oxygenated interface on biomass burn tar balls determined by single particle scanning transmission X-ray microscopy.

    Science.gov (United States)

    Tivanski, Alexei V; Hopkins, Rebecca J; Tyliszczak, Tolek; Gilles, Mary K

    2007-06-28

    Carbonaceous particles originating from biomass burning can account for a large fraction of organic aerosols in a local environment. Presently, their composition, physical and chemical properties, as well as their environmental effects are largely unknown. Tar balls, a distinct type of highly spherical carbonaceous biomass burn particles, have been observed in a number of field campaigns. The Yosemite Aerosol Characterization Study that took place in summer 2002 occurred during an active fire season in the western United States; tar balls collected during this field campaign are described in this article. Scanning transmission X-ray microscopy and near-edge X-ray absorption fine structure spectroscopy are used to determine the shape, structure, and size-dependent chemical composition of approximately 150 individual spherical particles ranging in size from 0.15 to 1.2 mum. The elemental composition of tar balls is approximately 55% atomic carbon and approximately 45% atomic oxygen. Oxygen is present primarily as carboxylic carbonyls and oxygen-substituted alkyl (O-alkyl-C) functional groups, followed by moderate amounts of ketonic carbonyls. The observed chemical composition, density, and carbon functional groups are distinctly different from soot or black carbon and more closely resemble high molecular weight polymeric humic-like substances, which could account for their reported optical properties. A detailed examination of the carboxylic carbonyl and O-alkyl-C functional groups as a function of particle size reveals a thin oxygenated interface layer. The high oxygen content, as well as the presence of water-soluble carboxylic carbonyl groups, could account for the reported hygroscopic properties of tar balls. The presence of the oxygenated layer is attributed to atmospheric processing of biomass burn particles.

  14. A comparison of surface roughness as measured by atomic force microscopy and x-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Munkholm, A.; Brennan, S. [Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center, Stanford, California 94309 (United States); Carr, E.C. [Hewlett-Packard Corporation, Palo Alto, California 94304 (United States)

    1997-09-01

    We compare measurements of the roughness of silicon(001) wafers cleaned by several methods. The roughness values were obtained using crystal truncation rod (CTR) scattering and atomic force microscopy. Although they do not yield identical results, both methods show the same relative roughness for the different cleans. CTR scattering is sensitive to roughness on lateral length scales down to atomic dimensions. The quantitative differences in roughness can be explained by the different wavelength spectrum of roughness probed by the two techniques. CTR measurements were also performed after a 60 {Angstrom} thermal oxide was grown on the wafers. The roughness trends are the same after oxidation, but we also find that the oxidation process has significantly reduced the interfacial roughness. {copyright} {ital 1997 American Institute of Physics.}

  15. Tracking Changes in Absorptivity, Stiffness, and Organic Chemical Composition in Laboratory Generated HULIS SOA using Atomic Force Microscopy and X-ray Microscopy

    Science.gov (United States)

    Hawkins, L. N.; Lemire, A.; Kong, W.

    2014-12-01

    Light absorbing organic compounds are among the many products of aqueous phase secondary organic aerosol formation. Once formed, these compounds can alter the optical and material properties of SOA in ways that impact their ability to scatter and absorb solar radiation, deliquesce and evaporate quickly during cloud cycling, and react with gas phase species such as oxidants. To quantify these effects, we have characterized the changes in UV-visible absorption, stiffness, and particle shape that occur when aqueous SOA is exposed to repeated wet-dry cycles and photooxidation. Material properties were measured with Atomic Force Microscopy of atomized laboratory generated SOA; this material was created by combining glyoxal, methylglyoxal, or glycolaldehyde with ammonium sulfate, glycine, or methylamine in solution and either spray drying or evaporating the bulk solution. In addition to optical and material properties, changes in organic functional groups were tracked using scanning transmission x-ray microscopy (STXM) of the near carbon edge x-ray absorption fine structure (NEXAFS). Photooxidation experiments of the same aqueous SOA revealed concomitant changes in the organic functional groups and light absorption spectra, along with measurable changes in particle stiffness.

  16. Intracellular concentration map of magnesium in whole cells by combined use of X-ray fluorescence microscopy and atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, Stefano, E-mail: stefano.lagomarsino@cnr.it [IPCF-CNR -UOS Roma c/o Dip Fisica Universita' ' Sapienza' , P.le A. Moro, 2 Rome (Italy); Physics Department, Universita' Sapienza, P.le A. Moro, 2 Rome (Italy); Iotti, Stefano [Dipartimento di Medicina Interna, dell' Invecchiamento e Malattie Nefrologiche Universita di Bologna, Via Massarenti, 9 40138 Bologna (Italy); Istituto Nazionale Biostrutture e Biosistemi - Rome (Italy); Farruggia, Giovanna [Dipartimento di Biochimica ' G. Moruzzi' Universita di Bologna, Via Irnerio, 48 40126 Bologna (Italy); Cedola, Alessia [IFN-CNR - V. Cineto Romano, 42 00156 Rome (Italy); Trapani, Valentina [Istituto di Patologia Generale - Universita Cattolica del Sacro Cuore - Facolta di Medicina ' A. Gemelli' L.go F. Vito, 1 00168 Rome (Italy); Fratini, Michela [IFN-CNR - V. Cineto Romano, 42 00156 Rome (Italy); Bukreeva, Inna [IFN-CNR - V. Cineto Romano, 42 00156 Rome (Italy); Shubnikov Institute of Crystallography, Leninskii prospekt 59, Moscow, 119333 (Russian Federation); Notargiacomo, Andrea [IFN-CNR - V. Cineto Romano, 42 00156 Rome (Italy); Mastrototaro, Lucia [Istituto di Patologia Generale - Universita Cattolica del Sacro Cuore - Facolta di Medicina ' A. Gemelli' L.go F. Vito, 1 00168 Rome (Italy); Marraccini, Chiara [Dipartimento di Medicina Interna, dell' Invecchiamento e Malattie Nefrologiche Universita di Bologna, Via Massarenti, 9 40138 Bologna (Italy); and others

    2011-11-15

    We report a novel experimental approach to derive quantitative concentration map of light elements in whole cells by combining two complementary nano-probe methods: X-ray fluorescence microscopy (XRFM) and atomic force microscopy (AFM). The concentration is derived by normalizing point-by-point the elemental (here Mg) spatial distribution obtained by XRFM, by the thickness measured using AFM. The considerable difference between the elemental distribution and the concentration maps indicates that this procedure is essential to obtain reliable information on the role and function of elements in whole cells. - Highlights: Black-Right-Pointing-Pointer X-ray fluorescence and AFM have been measured on the same de-hydrated whole cells. Black-Right-Pointing-Pointer The element distribution has been normalized point-by-point by the cell thickness. Black-Right-Pointing-Pointer The element (Mg) concentration map has been obtained on a whole cell. Black-Right-Pointing-Pointer The element concentration map is quite different from the distribution map. Black-Right-Pointing-Pointer Higher Mg concentration is found in the cell periphery.

  17. Use of energy-dispersive x-ray microanalysis as a rapid method for demarcating areas around marine outfalls that may be influenced by effluent: a case study

    CSIR Research Space (South Africa)

    Gregory, MA

    2005-01-01

    Full Text Available by Professor Peter A. Tanner, Professor in the Department of Biology and Chemistry at City University of Hong Kong. Address correspondence to Professor M. A. Gregory, Govan Mbeki Research Centre, University of Durban-Westville, Private Bag X54001, Durban 4000...- tial extraction scheme for Cu, Cr, Fe and Al speciation in marine particulates by scanning electron microscopy (SEM-EDX) and absorption and emission spec- troscopy (ETA-AAS and ICI-AES). In Proc. Congresso dell Assoziazione Italian di Oceanologia e...

  18. Element distribution and iron speciation in mature wheat grains (Triticum aestivum L.) using synchrotron X-ray fluorescence microscopy mapping and X-ray absorption near-edge structure (XANES) imaging.

    Science.gov (United States)

    De Brier, Niels; Gomand, Sara V; Donner, Erica; Paterson, David; Smolders, Erik; Delcour, Jan A; Lombi, Enzo

    2016-08-01

    Several studies have suggested that the majority of iron (Fe) and zinc (Zn) in wheat grains are associated with phytate, but a nuanced approach to unravel important tissue-level variation in element speciation within the grain is lacking. Here, we present spatially resolved Fe-speciation data obtained directly from different grain tissues using the newly developed synchrotron-based technique of X-ray absorption near-edge spectroscopy imaging, coupling this with high-definition μ-X-ray fluorescence microscopy to map the co-localization of essential elements. In the aleurone, phosphorus (P) is co-localized with Fe and Zn, and X-ray absorption near-edge structure imaging confirmed that Fe is chelated by phytate in this tissue layer. In the crease tissues, Zn is also positively related to P distribution, albeit less so than in the aleurone. Speciation analysis suggests that Fe is bound to nicotianamine rather than phytate in the nucellar projection, and that more complex Fe structures may also be present. In the embryo, high Zn concentrations are present in the root and shoot primordium, co-occurring with sulfur and presumably bound to thiol groups. Overall, Fe is mainly concentrated in the scutellum and co-localized with P. This high resolution imaging and speciation analysis reveals the complexity of the physiological processes responsible for element accumulation and bioaccessibility.

  19. Silicon location through backscattered electron imaging and X-ray microanalysis in leaves of Cyperus ligularis L. and Rhynchospora aberrans C. B. Clarke (Cyperaceae) Localização de sílica por elétrons retroespalhados em folhas de Cyperus ligularis L. and Rhynchospora aberrans C. B. Clarke (Cyperaceae)

    OpenAIRE

    Maria Emília Maranhão Estelita; Ana Claudia Rodrigues

    2012-01-01

    (Silicon location through backscattered electron imaging and X-ray microanalysis in leaves of Cyperus ligularis L. and Rhynchospora aberrans C. B. Clarke (Cyperaceae)). The Cyperaceae show the ability to incorporate silicon by depositing colloidal silica, which is recorded by the occurrence of projections in the form of cones, in inner tangential walls of some epidermal cells or "silica cells". Leaves of C. ligularis and R. aberrans were analyzed through the technique of electron backscatter....

  20. MICROSIRCCTORE CHARACTERISTIC AND X-RAY ENERGY DLSPERSIVE MICROANALYSIS OF CO-COMBUSTION FLY ASH OF BIOMASS WITH COAL%生物质垃圾与煤混烧飞灰颗粒的微观形态特征及能谱研究

    Institute of Scientific and Technical Information of China (English)

    任福民; 高明; 张玉磊; 于敏; 许兆义; 汝宜红

    2009-01-01

    The microstructure characteristic and elements analysis of the fly ash from co-combustion of biomass with coal was conducted by using scanning electron microscopy (SEM) and energy disperse X-ray microanalysis (EDX) . The re-sults show that the shapes of fly ash particles are multiple, most particles are irregular and the phenomenon of particle ad-sorption existed among different grain sizes. Potassium was detected in all fly ash particle. This means that the primarily existent form of potassium is potassium chloride in co-combustion of biomass with coal.%利用扫描电镜(SEM)和能谱(EDX)结合联用技术直观地观察了生物质垃圾与煤混合压制燃料的飞灰微观形态特征,分析了其主要组成元素及其质量分数.实验结果表明,飞灰颗粒的形态多样,以不规则形态居多.不同粒径颗粒之间存在逐级吸附的现象.在本实验观察的所有飞灰颗粒的能谱分析中都发现了K元素的存在.实验发现,生物质与煤混烧排放钾的主要存在形式是氯化钾.

  1. Detecting element specific electrons from a single cobalt nanocluster with synchrotron x-ray scanning tunneling microscopy

    Science.gov (United States)

    Kersell, Heath; Shirato, Nozomi; Cummings, Marvin; Chang, Hao; Miller, Dean; Rosenmann, Daniel; Hla, Saw-Wai; Rose, Volker

    2017-09-01

    We use a nanofabricated scanning tunneling microscope tip as a detector to investigate local X-ray induced tunneling and electron emission from a single cobalt nanocluster on a Au(111) surface. The tip-detector is positioned a few angstroms above the nanocluster, and ramping the incident X-ray energy across the Co photoabsorption K-edge enables the detection of element specific electrons. Atomic-scale spatial dependent changes in the X-ray absorption cross section are directly measured by taking the X-ray induced current as a function of X-ray energy. From the measured sample and tip currents, element specific X-ray induced current components can be separated and thereby the corresponding yields for the X-ray induced processes of the single cobalt nanocluster can be determined. The detection of element specific synchrotron X-ray induced electrons of a single nanocluster opens an avenue for materials characterization on a one particle at-a-time basis.

  2. Humidity-controlled preparation of frozen-hydrated biological samples for cryogenic coherent x-ray diffraction microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Yuki; Nakasako, Masayoshi [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan); RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148 (Japan)

    2012-05-15

    Coherent x-ray diffraction microscopy (CXDM) has the potential to visualize the structures of micro- to sub-micrometer-sized biological particles, such as cells and organelles, at high resolution. Toward advancing structural studies on the functional states of such particles, here, we developed a system for the preparation of frozen-hydrated biological samples for cryogenic CXDM experiments. The system, which comprised a moist air generator, microscope, micro-injector mounted on a micromanipulator, custom-made sample preparation chamber, and flash-cooling device, allowed for the manipulation of sample particles in the relative humidity range of 20%-94%rh at 293 K to maintain their hydrated and functional states. Here, we report the details of the system and the operation procedure, including its application to the preparation of a frozen-hydrated chloroplast sample. Sample quality was evaluated through a cryogenic CXDM experiment conducted at BL29XUL of SPring-8. Taking the performance of the system and the quality of the sample, the system was suitable to prepare frozen-hydrated biological samples for cryogenic CXDM experiments.

  3. Non-invasive airway health measurement using synchrotron x-ray microscopy of high refractive index glass microbeads

    Energy Technology Data Exchange (ETDEWEB)

    Donnelley, Martin, E-mail: martin.donnelley@adelaide.edu.au; Farrow, Nigel; Parsons, David [Respiratory & Sleep Medicine, Women’s and Children’s Hospital, North Adelaide, South Australia (Australia); Robinson Research Institute, University of Adelaide, South Australia (Australia); School of Paediatrics and Reproductive Health, University of Adelaide, South Australia (Australia); Morgan, Kaye; Siu, Karen [School of Physics, Monash University, Victoria (Australia)

    2016-01-28

    Cystic fibrosis (CF) is caused by a gene defect that compromises the ability of the mucociliary transit (MCT) system to clear the airways of debris and pathogens. To directly characterise airway health and the effects of treatments we have developed a synchrotron X-ray microscopy method that non-invasively measures the local rate and patterns of MCT behaviour. Although the nasal airways of CF mice exhibit the CF pathophysiology, there is evidence that nasal MCT is not altered in CF mice1. The aim of this experiment was to determine if our non-invasive local airway health assessment method could identify differences in nasal MCT rate between normal and CF mice, information that is potentially lost in bulk MCT measurements. Experiments were performed on the BL20XU beamline at the SPring-8 Synchrotron in Japan. Mice were anaesthetized, a small quantity of micron-sized marker particles were delivered to the nose, and images of the nasal airways were acquired for 15 minutes. The nasal airways were treated with hypertonic saline or mannitol to increase surface hydration and MCT. Custom software was used to locate and track particles and calculate individual and bulk MCT rates. No statistically significant differences in MCT rate were found between normal and CF mouse nasal airways or between treatments. However, we hope that the improved sensitivity provided by this technique will accelerate the ability to identify useful CF lung disease-modifying interventions in small animal models, and enhance the development and efficacy of proposed new therapies.

  4. X-ray tomographic microscopy tightens affinity of the early Cambrian Oymurania to the brachiopod stem group

    Directory of Open Access Journals (Sweden)

    Artem Kouchinsky

    2017-03-01

    Full Text Available The geologically rapid biotic evolution in the early Cambrian is marked by the first appearance of major groups of animals in the fossil record (e.g., Budd and Jensen 2000; Kouchinsky et al. 2012. Along with the earliest crown-group representatives of the phylum Brachiopoda, more basal branches of the phylogenetic tree belonging to the stem-group Brachiopoda, such as tannuolinids and mikwitziids, diversified and became widespread during the early Cambrian (e.g., Williams and Holmer 2002; Balthasar et al. 2009; Skovsted et al. 2014. Synchrotron-radiation X-ray tomographic microscopy (SRXTM of Oymurania gravestocki reveals the microstructure of its calcium-phosphatic shell differentiated into two layers and intersecting systems of canals. The outer layer shows the acrotretoid columnar microstructure and the inner layer consists of continuous prismatic columns. Phosphatized setae preserved within tangential canals, as well as perpendicular canals of Micrina–Setatella type demonstrate homology with the tannuolinid Micrina and the mickwitziid Setatella. A unique and novel combination of microstructural features in Oymurania confirms its evolutionary position within the brachiopod stem group.

  5. The internal structure of Early Cambrian fossil embryo Olivooides revealed in the light of Synchrotron X-ray Tomographic Microscopy

    Institute of Scientific and Technical Information of China (English)

    CHEN Fang; DONG XiPing

    2008-01-01

    Countless fossil embryo Olivooides and the hatched larvae, juveniles and adults (the latter two kinds are Punctatus) are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section, near Kuanchuanpu Village, Ningqiang County, Shaanxi Province, China. Using the technique of Synchrotron X-ray Tomographic Microscopy, the 3D internal structure of Olivooides and Punctatus is reconstructed. The morphological and statistic analyses are also given to the stellae structure of Olivooides and Punctatus, which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching, probably with the function of mucilage secretion. The internal structure of Punctatus is described and discussed. The ovum-like structure, a common internal feature of Punctatus, is considered as the taphonomic structure, rather than eggs or other biological structure. This structure is thought to be formed after the burial of the animal and before or during the mineralization. The original internal structure of Punctatus is assumed to be tabulae-filled, with soft body grown on them.

  6. Characterization of wood dust from furniture by scanning electron microscopy and energy-dispersive x-ray analysis.

    Science.gov (United States)

    Gómez Yepes, Milena Elizabeth; Cremades, Lázaro V

    2011-01-01

    Study characterized and analyzed form factor, elementary composition and particle size of wood dust, in order to understand its harmful health effects on carpenters in Quindío (Colombia). Once particle characteristics (size distributions, aerodynamic equivalent diameter (D(α)), elemental composition and shape factors) were analyzed, particles were then characterized via scanning electron microscopy (SEM) in conjunction with energy dispersive X-ray analysis (EDXRA). SEM analysis of particulate matter showed: 1) cone-shaped particle ranged from 2.09 to 48.79 µm D(α); 2) rectangular prism-shaped particle from 2.47 to 72.9 µm D(α); 3) cylindrically-shaped particle from 2.5 to 48.79 µm D(α); and 4) spherically-shaped particle from 2.61 to 51.93 µm D(α). EDXRA reveals presence of chemical elements from paints and varnishes such as Ca, K, Na and Cr. SEM/EDXRA contributes in a significant manner to the morphological characterization of wood dust. It is obvious that the type of particles sampled is a complex function of shapes and sizes of particles. Thus, it is important to investigate the influence of particles characteristics, morphology, shapes and D(α) that may affect the health of carpenters in Quindío.

  7. Localization of iron in rice grain using synchrotron X-ray fluorescence microscopy and high resolution secondary ion mass spectrometry

    KAUST Repository

    Kyriacou, Bianca

    2014-03-01

    Cereal crops accumulate low levels of iron (Fe) of which only a small fraction (5-10%) is bioavailable in human diets. Extensive co-localization of Fe in outer grain tissues with phytic acid, a strong chelator of metal ions, results in the formation of insoluble complexes that cannot be digested by humans. Here we describe the use of synchrotron X-ray fluorescence microscopy (XFM) and high resolution secondary ion mass spectrometry (NanoSIMS) to map the distribution of Fe, zinc (Zn), phosphorus (P) and other elements in the aleurone and subaleurone layers of mature grain from wild-type and an Fe-enriched line of rice (Oryza sativa L.). The results obtained from both XFM and NanoSIMS indicated that most Fe was co-localized with P (indicative of phytic acid) in the aleurone layer but that a small amount of Fe, often present as "hotspots", extended further into the subaleurone and outer endosperm in a pattern that was not co-localized with P. We hypothesize that Fe in subaleurone and outer endosperm layers of rice grain could be bound to low molecular weight chelators such as nicotianamine and/or deoxymugineic acid. © 2014.

  8. Interrogation of EGFR Targeted Uptake of TiO2 Nanoconjugates by X-ray Fluorescence Microscopy

    Science.gov (United States)

    Yuan, Ye; Paunesku, Tatjana; Arora, Hans; Ward, Jesse; Vogt, Stefan; Woloschak, Gayle

    2013-01-01

    We are developing TiO2 nanoconjugates that can be used as therapeutic and diagnostic agents. Nanoscale TiO2 can be surface conjugated with various molecules and has the unique ability to induce the production of reactive oxygen species after radiation activation. One way to improve the potential clinical usefulness of TiO2 nanoparticles is to control their delivery to malignant cells by targeting them to cancer cell specific antigens. Epidermal Growth Factor Receptor is one potential target that is enriched in epithelial cancers and is rapidly internalized after ligand binding. Hence, we have synthesized TiO2 nanoparticles and functionalized them with a short EGFR binding peptide to create EGFR-targeted NCs. X-ray Fluorescence Microscopy was used to image nanoconjugates within EGFR positive HeLa cells. Further labeling of fixed cells with antibodies against EGFR and Protein A nanogold showed that TiO2 nanoconjugates can colocalize with receptors at the cell’s plasma membrane. Interestingly, with increased incubation times, EGFR targeted nanoconjugates could also be found colocalized with EGFR within the cell nucleus. This suggests that EGFR-targeted nanoconjugates can bind the receptor at the cell membrane, which leads to the internalization of NC-receptor complexes and the subsequent transport of nanoconjugates into the nucleus. PMID:25284907

  9. Effective segmentation of fresh post-mortem murine lung parenchyma in phase contrast X-ray tomographic microscopy images

    Science.gov (United States)

    Vogiatzis Oikonomidis, Ioannis; Cremona, Tiziana P.; Lovric, Goran; Arcadu, Filippo; Stampanoni, Marco; Schittny, Johannes C.

    2017-06-01

    The acinus represents the functional unit of the mammalian lung. It is defined as the small tree of gas-exchanging airways, which is fed by the most distal purely conducting airway. Different hypotheses exist on how the fine structure of the acinus changes during ventilation and development. Since in classical 2-dimensional (2D) sections of the lung the borders of the acini are not detectable, every study of acini requires 3-dimensional (3D) datasets. As a basis for further studies of pulmonary acini we imaged rodent lungs as close to life as possible using phase contrast synchrotron radiation-based X-ray tomographic microscopy (SRXTM), and developed a protocol for the segmentation of the alveolar septa. The method is based on a combined multilevel filtering approach. Seeds are automatically defined for separate regions of tissue and airspace during each 2D filtering level and then given as input to a 3D random walk segmentation. Thus, the different types of artifacts present in the images are treated separately, taking into account the sample’s structural complexity. The proposed procedure yields high-quality 3D segmentations of acinar microstructure that can be used for a reliable morphological analysis.

  10. Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

    Science.gov (United States)

    Kirker, Grant; Zelinka, Sam; Gleber, Sophie-Charlotte; Vine, David; Finney, Lydia; Chen, Si; Hong, Young Pyo; Uyarte, Omar; Vogt, Stefan; Jellison, Jody; Goodell, Barry; Jakes, Joseph E.

    2017-01-01

    The role of ions in the fungal decay process of lignocellulose biomaterials, and more broadly fungal metabolism, has implications for diverse research disciplines ranging from plant pathology and forest ecology, to carbon sequestration. Despite the importance of ions in fungal decay mechanisms, the spatial distribution and quantification of ions in lignocellulosic cell walls and fungal hyphae during decay is not known. Here we employ synchrotron-based X-ray fluorescence microscopy (XFM) to map and quantify physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn, in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood, fungal hyphae with the dried extracellular matrix (ECM) from the fungus, and Ca oxalate crystals. Three-dimensional ion volume reconstructions were also acquired of wood cell walls and hyphae with ECM. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cell wall length scales. These measurements provide new insights into the movement of ions during decay and illustrate how synchrotron-based XFM is uniquely suited study these ions.

  11. Probing Co/Si interface behaviour by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this work, we investigate the Co-Si reaction, the Co growth mode at room temperature, diffusion behaviour as well as morphology evolution during annealing on both H-terminated and clean Si(001) and Si(111) surfaces. From in-situ X-ray photoelectron spectroscopy (XPS) investigation, "Co-Si" reaction appears to occur on both H-terminated and clean surfaces at room temperature (RT) and the silicide crystallinity is improved upon annealing.Co growth mode on H-terminated Si surfaces occurs in a pseudo layer-by-layer manner while small close-packed island growth mode is observed on the clean Si surface. Upon annealing at different temperatures, Co atom concentration decreases versus annealing time, which in part is attributed to Co atoms inward diffusion. The diffusion behaviour on both types of surfaces demonstrates a similar trend. Morphology study using ex-situ atomic force microscopy (AFM) shows that the islands formed on Si(001) surface after annealing at 700 ℃ are elongated with growth directions alternate between the two perpendicular [(-1)10] and [110] directions. Triangular islands are observed on Si(111) surface.

  12. NASA Li/CF(x) cell problem analysis: Scanning electron microscopy with energy dispersive x ray spectrometry

    Science.gov (United States)

    Baker, John

    1991-01-01

    An analysis was made of Lithium/carbon fluoride cell parts for possible chloride contamination induced by exposure to thionyl chloride (SOCl2); various samples were submitted for analysis. Only a portion of the analysis which has been conducted is covered, herein, namely analysis by scanning electron microscopy with energy dispersive x ray spectrometry (SEM/EDS). A strip of nickel was exposed to SOCl2 vapors to observe variations in surface concentrations of sulfur and chlorine with time. By detecting chlorine one can not infer contamination by SOCl2 only that contamination is present. Six samples of stainless steel foil were analyzed for chlorine using EDS. Chlorine was not detected on background samples but was detected on the samples which had been handled including those which had been cleaned. Cell covers suspected of being contaminated while in storage and covers which were not exposed to the same storage conditions were analyzed for chlorine. Although no chlorine was found on the covers from cells, it was found on all stored covers. Results are presented with techniques shown for analysis and identification. Relevant photomicrographs are presented.

  13. Synchrotron X-ray diffraction and scanning electron microscopy to understand enamel affected by metabolic disorder mucopolysaccharidosis.

    Science.gov (United States)

    Khan, Malik Arshman; Addison, Owen; James, Alison; Hendriksz, Christian J; Al-Jawad, Maisoon

    2016-04-01

    Mucopolysaccharidosis (MPS) is an inherited metabolic disorder that can affect the tooth structure leading to defects. Synchrotron X-ray diffraction being a state of the art technique has been used to determine the enamel crystallite orientation in deciduous enamel affected by Mucopolysaccharidosis Type I and Mucopolysaccharidosis Type IVA and comparing these with that of healthy deciduous enamel. Using this technique it was observed that there is a loss of texture in deciduous enamel affected by Mucopolysaccharidosis Type I and Mucopolysaccharidosis Type IVA when compared to the healthy deciduous enamel. Generally it was observed that the incisal surface of the deciduous teeth possessed a higher texture or preferred orientation of enamel crystallites and on progression towards the cervical region there was a decrease in the texture or preferred orientation of enamel crystallites. Scanning electron microscopy showed that the presence of a poorly calcified layer between the enamel and dentine at the enamel-dentine junction (EDJ) in MPS affected samples was likely to be responsible for rendering the tooth structure weak and prone to fracture as is often the case in MPS affected deciduous enamel.

  14. Elemental changes in the hippocampal formation following two different formulas of ketogenic diet: an X-ray fluorescence microscopy study.

    Science.gov (United States)

    Chwiej, J; Patulska, A; Skoczen, A; Janeczko, K; Ciarach, M; Simon, R; Setkowicz, Z

    2015-12-01

    The main purpose of the following study was the determination of elemental changes occurring within hippocampal formation as a result of high-fat and carbohydrate-restricted ketogenic diet (KD). To realize it, X-ray fluorescence microscopy was applied for topographic and quantitative analysis of P, S, K, Ca, Fe, Cu, Zn and Se in hippocampal formations taken from rats fed with two different KDs and naive controls. The detailed comparisons were done for sectors 1 and 3 of the Ammon's, the dentate gyrus and hilus of dentate gyrus. The results of elemental analysis showed that the KDs induced statistically significant changes in the accumulation of P, K, Ca, Zn and Se in particular areas of hippocampal formation and these alterations strongly depended on the composition of the diets. Much greater influence on the hippocampal areal densities of examined elements was found for the KD which was characterized by a lower content of carbohydrates, higher content of fats and increased proportion of unsaturated fatty acids. The levels of P, K and Zn decreased whilst those of Ca and Se increased as a result of the treatment with the KDs.

  15. Smectite flocculation structure modified by Al13 macro-molecules--as revealed by the transmission X-ray microscopy (TXM).

    Science.gov (United States)

    Zbik, Marek S; Martens, Wayde N; Frost, Ray L; Song, Yen-Fang; Chen, Yi-Ming; Chen, Jian-Hua

    2010-05-01

    The aggregate structure which occurs in aqueous smectitic suspensions is responsible for poor water clarification, difficulties in sludge dewatering and the unusual rheological behaviour of smectite rich soils. These macroscopic properties are dictated by the 3D structural arrangement of smectite finest fraction within flocculated aggregates. Here, we report results from a relatively new technique, transmission X-ray microscopy (TXM), which makes it possible to investigate the internal structure and 3D tomographic reconstruction of the smectite clay aggregates modified by Al(13) Keggin macro-molecule [Al(13)(O)(4)(OH)(24)(H(2)O)(12)](7+). Three different treatment methods were shown resulted in three different micro-structural environments of the resulting flocculation. In case of smectite sample prepared in Methods 1 and 3 particles fall into the primary minimum where Van der Waals forces act between FF oriented smectite flakes and aggregates become approach irreversible flocculation. In case of sample prepared using Method 2, particles contacting by edges (EE) and edge to face (EF) orientation fell into secondary minimum and weak flocculation resulted in severe gelation and formation of the micelle-like texture in fringe superstructure, which was first time observed in smectite based gel.

  16. Faults and foibles of quantitative scanning electron microscopy/energy dispersive x-ray spectrometry (SEM/EDS)

    Science.gov (United States)

    Newbury, Dale E.; Ritchie, Nicholas W. M.

    2012-06-01

    Scanning electron microscopy with energy dispersive x-ray spectrometry (SEM/EDS) is a powerful and flexible elemental analysis method that can identify and quantify elements with atomic numbers > 4 (Be) present as major constituents (where the concentration C > 0.1 mass fraction, or 10 weight percent), minor (0.01history of more than 40 years, and the sophistication of modern analytical software, the method is vulnerable to serious shortcomings that can lead to incorrect elemental identifications and quantification errors that significantly exceed reasonable expectations. This paper will describe shortcomings in peak identification procedures, limitations on the accuracy of quantitative analysis due to specimen topography or failures in physical models for matrix corrections, and quantitative artifacts encountered in xray elemental mapping. Effective solutions to these problems are based on understanding the causes and then establishing appropriate measurement science protocols. NIST DTSA II and Lispix are open source analytical software available free at www.nist.gov that can aid the analyst in overcoming significant limitations to SEM/EDS.

  17. Evolution and Function of Dinosaur Teeth at Ultramicrostructural Level Revealed Using Synchrotron Transmission X-ray Microscopy

    Science.gov (United States)

    Wang, Chun-Chieh; Song, Yen-Fang; Song, Sheng-Rong; Ji, Qiang; Chiang, Cheng-Cheng; Meng, Qingjin; Li, Haibing; Hsiao, Kiko; Lu, Yi-Chia; Shew, Bor-Yuan; Huang, Timothy; Reisz, Robert R.

    2015-01-01

    The relationship between tooth form and dietary preference is a crucial issue in vertebrate evolution. However, the mechanical properties of a tooth are influenced not only by its shape but also by its internal structure. Here, we use synchrotron transmission X-ray microscopy to examine the internal microstructures of multiple dinosaur teeth within a phylogenetic framework. We found that the internal microstructures of saurischian teeth are very different from advanced ornithischian teeth, reflecting differences in dental developmental strategies. The three-tissue composition (enamel–mantle dentin–bulk dentin) near the dentinoenamel junction (DEJ) in saurischian teeth represents the primitive condition of dinosaur teeth. Mantle dentin, greatly reduced or absent from DEJ in derived ornithischian teeth, is a key difference between Saurischia and Ornithischia. This may be related to the derived herbivorous feeding behavior of ornithischians, but interestingly, it is still retained in the herbivorous saurischian sauropods. The protective functions of mantle dentin with porous microstructures between enamel and bulk dentin inside typical saurischian teeth are also discussed using finite-element analysis method. Evolution of the dental modifications in ornithischian dinosaurs, with the absence of mantle dentin, may be related to changes in enamel characteristics with enamel spindles extending through the DEJ. PMID:26512629

  18. Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

    Science.gov (United States)

    Kirker, Grant; Zelinka, Sam; Gleber, Sophie-Charlotte; Vine, David; Finney, Lydia; Chen, Si; Hong, Young Pyo; Uyarte, Omar; Vogt, Stefan; Jellison, Jody; Goodell, Barry; Jakes, Joseph E.

    2017-01-01

    The role of ions in the fungal decay process of lignocellulose biomaterials, and more broadly fungal metabolism, has implications for diverse research disciplines ranging from plant pathology and forest ecology, to carbon sequestration. Despite the importance of ions in fungal decay mechanisms, the spatial distribution and quantification of ions in lignocellulosic cell walls and fungal hyphae during decay is not known. Here we employ synchrotron-based X-ray fluorescence microscopy (XFM) to map and quantify physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn, in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood, fungal hyphae with the dried extracellular matrix (ECM) from the fungus, and Ca oxalate crystals. Three-dimensional ion volume reconstructions were also acquired of wood cell walls and hyphae with ECM. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cell wall length scales. These measurements provide new insights into the movement of ions during decay and illustrate how synchrotron-based XFM is uniquely suited study these ions. PMID:28139778

  19. X-ray photoelectron spectroscopy and transmission electron microscopy analysis of silver-coated gold nanorods designed for bionanotechnology applications

    Science.gov (United States)

    Watanabe, Fumiya; Nima, Zeid A.; Honda, Takumi; Mitsuhara, Masatoshi; Nishida, Minoru; Biris, Alexandru S.

    2017-01-01

    Multicomponent nano-agents were designed and built via a core-shell approach to enhance their surface enhanced Raman scattering (SERS) signals. These nano-agents had 36 nm × 12 nm gold nanorod cores coated by 4 nm thick silver shell films and a subsequent thin bifunctional thiolated polyethylene glycol (HS-PEG-COOH) layer. Ambient time-lapsed SERS signal measurements of these functionalized nanorods taken over a two-week period indicated no signal degradation, suggesting that large portions of the silver shells remained in pure metallic form. The morphology of the nanorods was characterized by transmission electron microscopy (TEM) and ultra-high resolution scanning TEM. X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) were utilized to assess the oxidation states of the silver shells covered by HS-PEG-COOH. The binding energies of Ag 3d XPS spectra yielded very small chemical shifts with oxidation; however, the AES peak shapes gave meaningful information about the extent of oxidation undergone by the nano-agent. While the silver shells without HS-PEG-COOH coatings oxidized significantly, the silver shells with HS-PEG-COOH remained predominantly metallic. In fact, six month-old samples still retained mostly metallic silver shells. These findings further demonstrate the stability and longevity of the nanostructures, indicating their significant potential as plasmonically active agents for highly sensitive detection in various biological systems, including cancer cells, tissues, or even organisms.

  20. NASA Li/CF(x) cell problem analysis: Scanning electron microscopy with energy dispersive x ray spectrometry

    Science.gov (United States)

    Baker, John

    1991-01-01

    An analysis was made of Lithium/carbon fluoride cell parts for possible chloride contamination induced by exposure to thionyl chloride (SOCl2); various samples were submitted for analysis. Only a portion of the analysis which has been conducted is covered, herein, namely analysis by scanning electron microscopy with energy dispersive x ray spectrometry (SEM/EDS). A strip of nickel was exposed to SOCl2 vapors to observe variations in surface concentrations of sulfur and chlorine with time. By detecting chlorine one can not infer contamination by SOCl2 only that contamination is present. Six samples of stainless steel foil were analyzed for chlorine using EDS. Chlorine was not detected on background samples but was detected on the samples which had been handled including those which had been cleaned. Cell covers suspected of being contaminated while in storage and covers which were not exposed to the same storage conditions were analyzed for chlorine. Although no chlorine was found on the covers from cells, it was found on all stored covers. Results are presented with techniques shown for analysis and identification. Relevant photomicrographs are presented.

  1. Evolution and Function of Dinosaur Teeth at Ultramicrostructural Level Revealed Using Synchrotron Transmission X-ray Microscopy.

    Science.gov (United States)

    Wang, Chun-Chieh; Song, Yen-Fang; Song, Sheng-Rong; Ji, Qiang; Chiang, Cheng-Cheng; Meng, Qingjin; Li, Haibing; Hsiao, Kiko; Lu, Yi-Chia; Shew, Bor-Yuan; Huang, Timothy; Reisz, Robert R

    2015-10-29

    The relationship between tooth form and dietary preference is a crucial issue in vertebrate evolution. However, the mechanical properties of a tooth are influenced not only by its shape but also by its internal structure. Here, we use synchrotron transmission X-ray microscopy to examine the internal microstructures of multiple dinosaur teeth within a phylogenetic framework. We found that the internal microstructures of saurischian teeth are very different from advanced ornithischian teeth, reflecting differences in dental developmental strategies. The three-tissue composition (enamel-mantle dentin-bulk dentin) near the dentinoenamel junction (DEJ) in saurischian teeth represents the primitive condition of dinosaur teeth. Mantle dentin, greatly reduced or absent from DEJ in derived ornithischian teeth, is a key difference between Saurischia and Ornithischia. This may be related to the derived herbivorous feeding behavior of ornithischians, but interestingly, it is still retained in the herbivorous saurischian sauropods. The protective functions of mantle dentin with porous microstructures between enamel and bulk dentin inside typical saurischian teeth are also discussed using finite-element analysis method. Evolution of the dental modifications in ornithischian dinosaurs, with the absence of mantle dentin, may be related to changes in enamel characteristics with enamel spindles extending through the DEJ.

  2. Threshold for ion movements in wood cell walls below fiber saturation observed by X-ray fluorescence microscopy (XFM)

    Energy Technology Data Exchange (ETDEWEB)

    Zelinka, Samuel L.; Gleber, Sophie-Charlotte; Vogt, Stefan; Rodriguez Lopez, Gabriela M.; Jakes, Joseph E.

    2015-05-01

    Diffusion of chemicals and ions through the wood cell wall plays an important role in wood damage mechanisms. In the present work, free diffusion of ions through wood secondary walls and middle lamellae has been investigated as a function of moisture content (MC) and anatomical direction. Various ions (K, Cl, Zn, Cu) were injected into selected regions of 2 mu m thick wood sections with a microinjector and then the ion distribution was mapped by means of X-ray fluorescence microscopy with submicron spatial resolution. The MC of the wood was controlled in situ by means of climatic chamber with controlled relative humidity (RH). For all ions investigated, there was a threshold RH below which the concentration profiles did not change. The threshold RH depended upon ionic species, cell wall layer, and wood anatomical orientation. Above the threshold RH, differences in mobility among ions were observed and the mobility depended upon anatomical direction and cell wall layer. These observations support a recently proposed percolation model of electrical conduction in wood. The results contribute to understanding the mechanisms of fungal decay and fastener corrosion that occur below the fiber saturation point.

  3. Scanning transmission X-ray microscopy of nano structured thin film catalysts for proton-exchange-membrane fuel cells

    Science.gov (United States)

    Lee, Vincent; Berejnov, Viatcheslav; West, Marcia; Kundu, Sumit; Susac, Darija; Stumper, Jürgen; Atanasoski, Radoslav T.; Debe, Mark; Hitchcock, Adam P.

    2014-10-01

    Scanning transmission X-ray microscopy (STXM) has been applied to characterize nano structured thin film (NSTF) catalysts implemented as electrode materials in proton-exchange-membrane (PEM) fuel cells. STXM is used to study all chemical constituents at various stages in the fabrication process, from the perylene red (PR149) starting material, through the formation of the uncoated perylene whiskers, their coated form with Pt-based catalyst, and toward the NSTF anode fully integrated into the catalyst coated membrane (CCM). CCM samples were examined prior to operational testing and after several different accelerated testing protocols: start-up/shut-down (SU/SD), and reversal tests. It was found that, while the perylene support material is present in the pre-test samples, it was completely absent in the post-test samples. We attribute this loss of perylene material to the presence of cracks in the catalyst combined with intensive hydrogenation processes happening at the anode during operation. Despite the loss of the perylene support, the platinum shells forming the NSTF anode catalyst layer performed well during the tests.

  4. Exceptionally preserved Cambrian trilobite digestive system revealed in 3D by synchrotron-radiation X-ray tomographic microscopy.

    Directory of Open Access Journals (Sweden)

    Mats E Eriksson

    Full Text Available The Cambrian 'Orsten' fauna comprises exceptionally preserved and phosphatised microscopic arthropods. The external morphology of these fossils is well known, but their internal soft-tissue anatomy has remained virtually unknown. Here, we report the first non-biomineralised tissues from a juvenile polymerid trilobite, represented by digestive structures, glands, and connective strands harboured in a hypostome from the Swedish 'Orsten' fauna. Synchrotron-radiation X-ray tomographic microscopy enabled three-dimensional internal recordings at sub-micrometre resolution. The specimen provides the first unambiguous evidence for a J-shaped anterior gut and the presence of a crop with a constricted alimentary tract in the Trilobita. Moreover, the gut is Y-shaped in cross section, probably due to a collapsed lumen of that shape, another feature which has not previously been observed in trilobites. The combination of anatomical features suggests that the trilobite hypostome is functionally analogous to the labrum of euarthropods and that it was a sophisticated element closely integrated with the digestive system. This study also briefly addresses the preservational bias of the 'Orsten' fauna, particularly the near-absence of polymerid trilobites, and the taphonomy of the soft-tissue-harbouring hypostome.

  5. 钢铁厂废旧除尘滤袋的微观结构特征及能谱分析%Microstructure features and X-ray spectroscopy microanalysis of the sewage-filtering bags in steel works

    Institute of Scientific and Technical Information of China (English)

    周云; 宁寻安; 刘敬勇; 王江辉; 陈海斌; 廖希凯

    2012-01-01

    在废旧除尘滤袋中重金属总量测定方法的研究基础上,采用扫描电镜-能谱分析(SEM-EDS)对广东某钢铁厂不同工序中废旧除尘滤袋的微观结构及元素浓度进行试验研究,以确定其表面形态以及成分组成.结果表明,钢铁厂废旧除尘滤袋表面颗粒形态多样,以球形体、絮状集合体居多,含有结晶态和一些不规则的聚合体.通过扫描电镜(SEM)图像可以看出,经机械拍打后的废旧除尘滤袋上仍不同程度的附着着粉尘,并与滤袋结合紧密.根据图谱上出现的亮点,可推测其可能含有重金属等有毒有害物质.通过对废旧除尘滤袋进行能谱(EDS)分析可知,废旧除尘滤袋表面飞灰颗粒中以C、O、Fe、Si、Ca、Mg为主,并含有少量Pb、Cd、Zn、Ni等重金属.%This paper is aimed at a study of Microstructure Features and X-Ray energy-spectroscopy dispersive microanalysis of the sewage-filtering bags in steel works. We have made the above said microanalysis of five kinds of sewage-filtering bags from a steel mill in Guangdong by using an electronic scanning microscope ( ESM) and energy-dispersive X-ray spectroscopy (EDS). The whole analysis has been done on the basis of our previous research experience for measuring and determining the total amount of heavy metals and the pfe-treatment effect of the bags. The results of our investigation indicate that the shapes of the surface particles from the filtering bags turn out to be various; most of them are spherical and flocculent in a crystallized state while some others are irregular mixtures. From their images under the ESM, it can be seen that they are remaining dusts at differr ent levels of particles after flapping pretreatment, and closely combined with the bags. This indicates that the particulate matters in the filtering bags were mainly coming from the fly-ashes attached to the outside and inside of the bags, which are actually remnants of different constituent elements of

  6. X-ray microscopy as an approach to increasing accuracy and efficiency of serial block-face imaging for correlated light and electron microscopy of biological specimens.

    Science.gov (United States)

    Bushong, Eric A; Johnson, Donald D; Kim, Keun-Young; Terada, Masako; Hatori, Megumi; Peltier, Steven T; Panda, Satchidananda; Merkle, Arno; Ellisman, Mark H

    2015-02-01

    The recently developed three-dimensional electron microscopic (EM) method of serial block-face scanning electron microscopy (SBEM) has rapidly established itself as a powerful imaging approach. Volume EM imaging with this scanning electron microscopy (SEM) method requires intense staining of biological specimens with heavy metals to allow sufficient back-scatter electron signal and also to render specimens sufficiently conductive to control charging artifacts. These more extreme heavy metal staining protocols render specimens light opaque and make it much more difficult to track and identify regions of interest (ROIs) for the SBEM imaging process than for a typical thin section transmission electron microscopy correlative light and electron microscopy study. We present a strategy employing X-ray microscopy (XRM) both for tracking ROIs and for increasing the efficiency of the workflow used for typical projects undertaken with SBEM. XRM was found to reveal an impressive level of detail in tissue heavily stained for SBEM imaging, allowing for the identification of tissue landmarks that can be subsequently used to guide data collection in the SEM. Furthermore, specific labeling of individual cells using diaminobenzidine is detectable in XRM volumes. We demonstrate that tungsten carbide particles or upconverting nanophosphor particles can be used as fiducial markers to further increase the precision and efficiency of SBEM imaging.

  7. A description of Echinorhynchus baeri Kostylew, 1928 (Acanthocephala: Echinorhynchidae from Salmo trutta in Turkey, with notes on synonymy, geographical origins, geological history, molecular profile, and X-ray microanalysis

    Directory of Open Access Journals (Sweden)

    Amin Omar M.

    2016-01-01

    Full Text Available A population of Echinorhynchus baeri Kostylew, 1928 with 18–24 rows of 8–10 proboscis hooks each and long fusiform eggs measuring 95–110 × 18–22 μm collected from Salmo trutta (Salmonidae in a branch of the Murat River in Turkey is described and specimens are designated as neotype. Specimens of two similar populations of E. baeri (E. baeri Kostylew, 1928 and E. sevani Dinnik, 1932 were previously described from Salmo ischchan in Lake Sevan, Armenia. Waters of Lake Sevan and the Murat River were previously joined during the Middle Miocene-Pliocene. The two populations from Lake Sevan and ours from Turkey had identical morphology and size eggs. The proboscis armature and eggs, among other features of our Turkish specimens, proved intermediate between E. baeri and E. sevani, thus eliminating the significance of the described differences between these two species and confirming their synonymy with priority to Echinorhynchus baeri (junior synonym: Echinorhynchus sevani Dinnik, 1932. Echinorhynchus baeri is apparently a highly variable species. The two descriptions from Lake Sevan did not include features or illustrations of females, except for references to trunk and egg size but the eggs were illustrated. Complete morphometric comparisons are made and females of the Turkish material are described for the first time. DNA sequencing (mitochondrial cytochrome oxidase subunit I gene; nuclear 18S rRNA gene results from two available E. baeri individuals were equivocal. New features to the Acanthocephala include the presence of rootless uncalcified apical proboscis hooks studied with X-ray microanalysis.

  8. Scanning ion-selective electrode technique and X-ray microanalysis provide direct evidence of contrasting Na+ transport ability from root to shoot in salt-sensitive cucumber and salt-tolerant pumpkin under NaCl stress.

    Science.gov (United States)

    Lei, Bo; Huang, Yuan; Sun, Jingyu; Xie, Junjun; Niu, Mengliang; Liu, Zhixiong; Fan, Molin; Bie, Zhilong

    2014-12-01

    Grafting onto salt-tolerant pumpkin rootstock can increase cucumber salt tolerance. Previous studies have suggested that this can be attributed to pumpkin roots with higher capacity to limit the transport of Na(+) to the shoot than cucumber roots. However, the mechanism remains unclear. This study investigated the transport of Na(+) in salt-tolerant pumpkin and salt-sensitive cucumber plants under high (200 mM) or moderate (90 mM) NaCl stress. Scanning ion-selective electrode technique showed that pumpkin roots exhibited a higher capacity to extrude Na(+), and a correspondingly increased H(+) influx under 200 or 90 mM NaCl stress. The 200 mM NaCl induced Na(+)/H(+) exchange in the root was inhibited by amiloride (a Na(+)/H(+) antiporter inhibitor) or vanadate [a plasma membrane (PM) H(+) -ATPase inhibitor], indicating that Na(+) exclusion in salt stressed pumpkin and cucumber roots was the result of an active Na(+)/H(+) antiporter across the PM, and the Na(+)/H(+) antiporter system in salt stressed pumpkin roots was sufficient to exclude Na(+) X-ray microanalysis showed higher Na(+) in the cortex, but lower Na(+) in the stele of pumpkin roots than that in cucumber roots under 90 mM NaCl stress, suggesting that the highly vacuolated root cortical cells of pumpkin roots could sequester more Na(+), limit the radial transport of Na(+) to the stele and thus restrict the transport of Na(+) to the shoot. These results provide direct evidence for pumpkin roots with higher capacity to limit the transport of Na(+) to the shoot than cucumber roots.

  9. Application of Scanning-Imaging X-Ray Microscopy to Fluid Inclusion Candidates in Carbonates of Carbonaceous Chondrites

    Science.gov (United States)

    Tsuchiyama, Akira; Nakano, Tsukasa; Miyake, Akira; Akihisa, Takeuchi; Uesugi, Kentaro; Suzuki, Yoshio; Kitayama, Akira; Matsuno, Junya; Zolensky, Michael E.

    2016-01-01

    In order to search for such fluid inclusions in carbonaceous chondrites, a nondestructive technique using x-ray micro-absorption tomography combined with FIB sampling was developed and applied to a carbonaceous chondrite. They found fluid inclusion candidates in calcite grains, which were formed by aqueous alteration. However, they could not determine whether they are really aqueous fluids or merely voids. Phase and absorption contrast images can be simultaneously obtained in 3D by using scanning-imaging x-ray microscopy (SIXM). In refractive index, n=1-sigma+i(beta), in the real part, 1-sigma is the refractive index with decrement, sigma, which is nearly proportional to the density, and the imaginary part, beta, is the extinction coefficient, which is related to the liner attenuation coefficient, mu. Many phases, including water and organic materials as well as minerals, can be identified by SIXM, and this technique has potential availability for Hayabusa-2 sample analysis too. In this study, we examined quantitative performance of d and m values and the spatial resolution in SIXM by using standard materials, and applied this technique to carbonaceous chondrite samples. We used POM ([CH2O]n), silicon, quartz, forsterite, corundum, magnetite and nickel as standard materials for examining the sigma and mu values. A fluid inclusion in terrestrial quartz and bi-valve shell (Atrina vexillum), which are composed of calcite and organic layers with different thickness, were also used for examining the spatial resolution. The Ivuna (CI) and Sutter's Mill (CM) meteorites were used as carbonaceous chondrite samples. Rod- or cube-shaped samples 20-30 micron in size were extracted by using FIB from cross-sectional surfaces of the standard materials or polished thin sections of the chondrites, which was previously observed with SEM. Then, the sample was attached to a thin W-needle and imaged by SIXM system at beamline BL47XU, SPring-8, Japan. The slice thickness was 109.3 nm

  10. Scanning electron microscopy, X-ray diffraction and thermal analysis study of the TiH{sub 2} foaming agent

    Energy Technology Data Exchange (ETDEWEB)

    Mandrino, Djordje, E-mail: djordje.mandrino@imt.si [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia); Paulin, Irena [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia); Skapin, Sreco D. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2012-10-15

    The decomposition of commercially available TiH{sub 2} was investigated while performing different thermal treatments. TiH{sub 2} powder, which is widely used as a foaming agent, was heat treated at 450 Degree-Sign C for various times, from 15 min to 120 min. Scanning electron microscopy (SEM) images of the surfaces at different magnifications were obtained and interpreted. A Bragg-Brentano X-ray diffractometer was used to measure the X-ray diffraction (XRD) spectra on all five samples. A close examination of the diffraction spectra showed that for an as-received sample and samples undergoing the longest thermal treatment (1 and 2 h) these spectra can be explained as deriving from cubic TiH{sub 1.924}, while for the other two samples they can be explained as deriving from tetragonal TiH{sub 1.924}. A constant-unit-cell-volume phase transition between the cubic and tetragonal phases in TiH{sub 2-y}-type compounds had been described in the literature. The unit-cell parameters obtained from measured spectra confirm that within the measurement uncertainty the unit-cell volume is indeed constant in all five samples. Thermo-gravimetry (TG) and differential thermal analysis (DTA) measurements were performed on all the samples, showing that the intensity of the dehydrogenation depends on the previous treatment of the TiH{sub 2}. After the thermal analysis XRD of the samples was performed again and the material was found to exhibit a Ti-like unit cell, but slightly enlarged due to the unreleased hydrogen. - Highlights: Black-Right-Pointing-Pointer TiH{sub 2} samples were cubic or tetragonal TiH{sub 1.924} Black-Right-Pointing-Pointer Onset of the hydrogen release temperature increases with the pre-treatment time. Black-Right-Pointing-Pointer Thermal dehydrogenation for the as-prepared TiH{sub 2} is a three-step process. Black-Right-Pointing-Pointer After thermal analysis 2 residual hydrogen TiH{sub x} phases, close to {alpha}Ti, appeared.

  11. Achromatic and high-resolution full-field X-ray microscopy based on total-reflection mirrors.

    Science.gov (United States)

    Matsuyama, Satoshi; Emi, Yoji; Kino, Hidetoshi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2015-04-20

    We developed an achromatic and high-resolution full-field X-ray microscope based on advanced Kirkpatrick-Baez mirror optics that comprises two pairs of elliptical mirrors and hyperbolic mirrors utilizing the total reflection of X-rays. Performance tests to investigate the spatial resolution and chromatic aberration were performed at SPring-8. The microscope clearly resolved the pattern with ~100-nm feature size. Imaging the pattern by changing the X-ray energy revealed achromatism in the wide energy range of 8-11 keV.

  12. Transmission photoemission electron microscopy for lateral mapping of the X-ray absorption structure of a metalloprotein in a liquid cell.

    Science.gov (United States)

    Panzer, D; Beck, C; Maul, J; Möller, M; Decker, H; Schönhense, G

    2008-11-01

    We use photoemission electron microscopy in an X-ray transmission mode for full-field imaging of the X-ray absorption structure of copper in the respiratory metalloprotein hemocyanin KLH1. It contains 160 oxygen binding sites. Each site reversibly binds one molecule oxygen between two copper atoms. In our setup, hemocyanin is dissolved in aqueous solution and enclosed in an ultra-high vacuum compatible liquid sample cell with silicon nitride membranes. The local X-ray absorption structure of the liquid sample is converted into photoelectrons at the microscope side of the cell acting as a photocathode. In this way, different copper valencies are laterally distinguished under in vivo-like conditions, attributed to Cu(I) in the deoxy-state and Cu(II) in the oxy-state.

  13. Thermal analysis, X-ray powder diffraction and electron microscopy data related with the production of 1:1 Caffeine:Glutaric Acid cocrystals

    Directory of Open Access Journals (Sweden)

    Íris Duarte

    2016-09-01

    Full Text Available The data presented in this article are related to the production of 1:1 Caffeine:Glutaric Acid cocrystals as part of the research article entitled “Green production of cocrystals using a new solvent-free approach by spray congealing” (Duarte et al., 2016 [1]. More specifically, here we present the thermal analysis and the X-ray powder diffraction data for pure Glutaric Acid, used as a raw material in [1]. We also include the X-ray powder diffraction and electron microscopy data obtained for the 1:1 Caffeine:Glutaric Acid cocrystal (form II produced using the cooling crystallization method reported in “Operating Regions in Cooling Cocrystallization of Caffeine and Glutaric Acid in Acetonitrile” (Yu et al., 2010 [2]. Lastly, we show the X-ray powder diffraction data obtained for assessing the purity of the 1:1 Caffeine:Glutaric cocrystals produced in [1].

  14. Synchrotron X-Ray Fluorescence Microscopy of Gallium in Bladder Tissue following Gallium Maltolate Administration during Urinary Tract Infection

    OpenAIRE

    Ball, Katherine R.; Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L.; Blyth, Robert I. R.; Sham, Tsun-Kong; Dowling, Patricia M.; Thompson, Julie

    2013-01-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived ...

  15. New highlights of phytolith structure and occluded carbon location: 3-D X-ray microscopy and NanoSIMS results

    Science.gov (United States)

    Alexandre, A.; Basile-Doelsch, I.; Delhaye, T.; Borshneck, D.; Mazur, J. C.; Reyerson, P.; Santos, G. M.

    2015-02-01

    Phytoliths contain occluded organic compounds called phytC. Recently, phytC content, nature, origin, paleoenvironmental meaning and impact in the global C cycle have been the subject of increasing debate. Inconsistencies were fed by the scarcity of in situ characterizations of phytC in phytoliths. Here we reconstructed at high spatial resolution the 3-D structure of harvested grass short cell (GSC) phytoliths using 3-D X-ray microscopy. While this technique has been widely used for 3-D reconstruction of biological systems it has never been applied in high-resolution mode to silica particles. Simultaneously, we investigated the location of phytC using nanoscale secondary ion mass spectrometry (NanoSIMS). Our data evidenced that the silica structure contains micrometric internal cavities. These internal cavities were sometimes observed isolated from the outside. Their opening may be an original feature or may result from a beginning of dissolution of silica during the chemical extraction procedure, mimicking the progressive dissolution process that can happen in natural environments. The phytC that may originally occupy the cavities is thus susceptible to rapid oxidation. It was not detected by the NanoSIMS technique. However, another pool of phytC, continuously distributed in and protected by the silica structure, was observed. Its N/C ratio (0.27) is in agreement with the presence of amino acids. These findings constitute a basis to further characterize the origin, occlusion process, nature and accessibility of phytC, as a prerequisite for assessing its significance in the global C cycle.

  16. Atomic level study of water-gas shift catalysts via transmission electron microscopy and x-ray spectroscopy

    Science.gov (United States)

    Akatay, Mehmed Cem

    Water-gas shift (WGS), CO + H2O ⇆ CO2 + H2 (DeltaH° = -41 kJ mol -1), is an industrially important reaction for the production of high purity hydrogen. Commercial Cu/ZnO/Al2O3 catalysts are employed to accelerate this reaction, yet these catalysts suffer from certain drawbacks, including costly regeneration processes and sulfur poisoning. Extensive research is focused on developing new catalysts to replace the current technology. Supported noble metals stand out as promising candidates, yet comprise intricate nanostructures complicating the understanding of their working mechanism. In this study, the structure of the supported Pt catalysts is explored by transmission electron microscopy and X-ray spectroscopy. The effect of the supporting phase and the use of secondary metals on the reaction kinetics is investigated. Structural heterogeneities are quantified and correlated with the kinetic descriptors of the catalysts to develop a fundamental understanding of the catalytic mechanism. The effect of the reaction environment on catalyst structure is examined by in-situ techniques. This study benefitted greatly from the use of model catalysts that provide a convenient medium for the atomic level characterization of nanostructures. Based on these studies, Pt supported on iron oxide nano islands deposited on inert spherical alumina exhibited 48 times higher WGS turnover rate (normalized by the total Pt surface area) than Pt supported on bulk iron oxide. The rate of aqueous phase glycerol reforming reaction of Pt supported on multiwall carbon nanotubes (MWCNT) is promoted by co-impregnating with cobalt. The synthesis resulted in a variety of nanostructures among which Pt-Co bimetallic nanoparticles are found to be responsible for the observed promotion. The unprecedented WGS rate of Pt supported on Mo2C is explored by forming Mo 2C patches on top of MWCNTs and the rate promotion is found to be caused by the Pt-Mo bimetallic entities.

  17. Chemical elements characterization of root canal sealers using scanning electron microscopy and energy dispersive X-ray analysis.

    Science.gov (United States)

    Sampaio, Felipe Cavalcanti; Alencar, Ana Helena Gonçalves; Guedes, Orlando Aguirre; Veloso, Heloisa Helena Pinho; Santos, Tatiane Oliveira; Estrela, Carlos

    2014-03-01

    The aim of this study was to evaluate the chemical elements composition of root canal filling materials using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Eighteen standard polyethylene tubes were filled with the following materials: Sealapex(®), Sealer 26(®), MTA Fillapex(®), Pulp Canal Sealer(®), Endofill(®) and AH Plus(®). After 48 hours at 37°C and 95% relative humidity, the samples were surface-sputtered with gold and analyzed using SEM at 5000X magnification. Their chemical composition and element distributionwere determined using EDX. Results were evaluated qualitatively (SEM images and elemental mapping) and quantitatively (weight percentage). Calcium oxide- and hydroxide-based sealers (Sealapex(®) and Sealer 26(®)) had calcium peaks of 53.58 wt% and 65.00 wt%. MTA Fillapex(®) had 30.58 wt% of calcium and high amounts of silicon (31.02 wt%) and bismuth (27.38 wt%). Zinc oxide- and eugenol-based sealers, Pulp Canal Sealer(®) and Endofill(®), had 67.74 wt% and 63.16 wt% of zinc each. AH Plus(®) had a higher amount of zirconium (64.24 wt%). All materials had elements other than those described by the manufacturers. Surface analysis using EDX revealed that regularity varied, element distribution was uniform, and particles had similar sizes and variable shapes. Most chemical elements were those described by the manufacturers, but percentages were different. The surface of root canal sealers had different regularity findings, uniform distribution and particles of similar sizes but variable shapes.

  18. Carbon corrosion of proton exchange membrane fuel cell catalyst layers studied by scanning transmission X-ray microscopy

    Science.gov (United States)

    Hitchcock, Adam P.; Berejnov, Viatcheslav; Lee, Vincent; West, Marcia; Colbow, Vesna; Dutta, Monica; Wessel, Silvia

    2014-11-01

    Scanning Transmission X-ray Microscopy (STXM) at the C 1s, F 1s and S 2p edges has been used to investigate degradation of proton exchange membrane fuel cell (PEM-FC) membrane electrode assemblies (MEA) subjected to accelerated testing protocols. Quantitative chemical maps of the catalyst, carbon support and ionomer in the cathode layer are reported for beginning-of-test (BOT), and end-of-test (EOT) samples for two types of carbon support, low surface area carbon (LSAC) and medium surface area carbon (MSAC), that were exposed to accelerated stress testing with upper potentials (UPL) of 1.0, 1.2, and 1.3 V. The results are compared in order to characterize catalyst layer degradation in terms of the amounts and spatial distributions of these species. Pt agglomeration, Pt migration and corrosion of the carbon support are all visualized, and contribute to differing degrees in these samples. It is found that there is formation of a distinct Pt-in-membrane (PTIM) band for all EOT samples. The cathode thickness shrinks due to loss of the carbon support for all MSAC samples that were exposed to the different upper potentials, but only for the most aggressive testing protocol for the LSAC support. The amount of ionomer per unit volume significantly increases indicating it is being concentrated in the cathode as the carbon corrosion takes place. S 2p spectra and mapping of the cathode catalyst layer indicates there are still sulfonate groups present, even in the most damaged material.

  19. New highlights on phytolith structure and occluded carbon location: 3-D X-ray microscopy and NanoSIMS results

    Science.gov (United States)

    Alexandre, A.; Basile-Doelsch, I.; Delhaye, T.; Borshneck, D.; Mazur, J. C.; Reyerson, P.; Santos, G. M.

    2014-10-01

    Phytoliths contain occluded organic compounds called phytC. Recently, phytC content, nature, origin, paleoenvironmental meaning and impact in the global C cycle has been the subject of increasing debate. Inconsistencies were fed by the scarcity of in-situ characterization of phytC in phytoliths. Here we reconstructed at high spatial resolution the 3-dimensional (3-D) structure of harvested grass short cell (GSC) phytoliths using 3-D X-ray microscopy. While this technic has been widely used for 3-D reconstruction of biological systems it has never been applied in high resolution mode to silica particles. Simultaneously, we investigated the location of phytC using Nano-scale Secondary Ion Mass Spectrometry (NanoSIMS). Our data evidenced that the silica structure contains micrometric internal cavities. These internal cavities were sometimes observed isolated from the outside. Their opening may be an original feature or may result from a beginning of dissolution of silica during the chemical extraction procedure, mimicking the progressive dissolution process that can happen in natural environments. The phytC that may originally occupy the cavities is thus susceptible to rapid oxidation. It was not detected by the nanoSIMS technique. To the contrary another pool of phytC, continuously distributed in and protected by the silica structure was evidenced. Its N/C ratio (0.27) is in agreement with the presence of amino acids. These findings allowed to discuss discrepancies in phytC quantification, evaluate phytC accessibility to oxidation, and reassess the paleo-environmental meaning of opaque features observed in phytoliths by natural light (NL) microcopy. They also should help to reappraise the significance of phytC in the global C cycle.

  20. Soft x-ray microscopy and extreme ultraviolet lithography: Imaging in the 20-50 nm regime (abstract) (invited)

    Science.gov (United States)

    Attwood, David

    2002-03-01

    Advances in short wavelength optics, covering the range from 1 to 14 nm, are providing new results and new opportunities. Zone plate lenses [E. Anderson et al., J. Vac. Sci. Techno. B 18, 2970 (2000)] for soft x-ray microscopy [G. Denbeaux, Rev. Sci. Instrum. (these proceedings); W. Chao, Proc. SPIE 4146, 171 (2000)] are now made to high accuracy with outer zone widths of 25 nm, and demonstrated resolution of 23 nm with proper illumination and stability. These permit important advances in the study of protein specific transport and structure in the life sciences [C. Larabell (private communication); W. Meyer-Ilse et al., J. Microsc. 201, 395 (2001)] and the study of magnetic materials [P. Fischer et al., J. Synchrotron. Radiat. 8, 325 (2001)] with elemental sensitivity at the resolution of individual domains. Major corporations (members of the EUV Limited Liability Company are Intel, Motorola, AMD, Micron, Infineon, and IBM) are now preparing the path for the fabrication of future computer chips, in the years 2007 and beyond, using multilayer coated reflective optics, which achieve reflectivities of 70% in the 11-14 nm region [T. Barbee et al., Appl. Opt. 24, 883 (1985); C. Montcalm et al., Proc. SPIE 3676, 710 (1999)]. These coated optics are to be incorporated in extreme ultraviolet (EUV) print cameras, known as "steppers." Electronic patterns with features in the range of 50-70 nm have been printed. The first alpha tool stepper recently demonstrated all critical technologies [D. Tichenor et al., Proc. SPIE 4343, 19 (2001)] needed for EUV lithography. Preproduction beta tools are targeted for delivery by leading suppliers [ASML, the Netherlands, at the SPIE Microlithography Conference, Santa Clara, CA, March 2001] in 2004, with high volume production tools available in late 2006 for manufacturing in 2007. New results in these two areas will be discussed in the context of the synergy of science and technology.

  1. Mineralization of human premolar occlusal fissures: a quantitative histochemical microanalysis

    OpenAIRE

    Campos, Antonio; Rodriguez, I. A.; Sanchez-Quevedo, M.C.; García, J. M.; Nieto-Albano, O.H.; Gómez de Ferraris, M. E.

    2000-01-01

    The mechanisms of cariogenesis in occlusal fissures remain elusive because of limited information about fissure structure and wall mineralization. The purpose of the present study was to determine the correlation between morphological patterns in occlusal fissures in human premolars and quantitative histochemical patterns of mineralization in the walls of these formations. We used scanning electron microscopy and quantitative X-ray microanalysis with the peak-t...

  2. Two-dimensional functional molecular nanoarchitectures - Complementary investigations with scanning tunneling microscopy and X-ray spectroscopy

    Science.gov (United States)

    Klappenberger, Florian

    2014-02-01

    Functional molecular nanoarchitectures (FMNs) are highly relevant for the development of future nanotechnology devices. Profound knowledge about the atomically controlled construction of such nanoscale assemblies is an indispensable requirement to render the implementation of such components into a real product successful. For exploiting their full potential the architectures’ functionalities have to be characterized in detail including the ways to tailor them. In recent years a plethora of sophisticated constructs were fabricated touching a wide range of research topics. The present review summarizes important achievements of bottom-up fabricated, molecular nanostructures created on single crystal metal surfaces under ultra-high vacuum conditions. This selection focuses on examples where self-assembly mechanisms played a central role for their construction. Such systems, though typically quite complex, can be comprehensively understood by the STM+XS approach combining scanning tunneling microscopy (STM) with X-ray spectroscopy (XS) and being aided in the atomic interpretation by the appropriate theoretic analysis, often from density functional theory. The symbiosis of the techniques is especially fruitful because of the complementary character of the information accessed by the local microscopy and the space-averaging spectroscopy tools. STM delivers sub-molecular spatial-resolution, but suffers from limited sensitivity for the chemical and conformational states of the building-blocks. XS compensates these weaknesses with element- and moiety-specific data, which in turn would be hard to interpret with respect to structure formation without the topographic details revealed by STM. The united merit of this methodology allows detailed geometric information to be obtained and addresses both the electronic and chemical state of the complex organic species constituting such architectures. Thus, possible changes induced by the various processes such as surface

  3. High-resolution dichroic imaging of magnetic flux distributions in superconductors with scanning x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ruoss, Stephen; Stahl, Claudia; Weigand, Markus; Schuetz, Gisela [Max-Planck-Institut fuer Intelligente Systeme, Stuttgart (Germany); Albrecht, Joachim [Research Institute for Innovative Surfaces, FINO, Aalen University (Germany)

    2015-07-01

    The penetration of magnetic flux into the high-temperature superconductor YBCO has been observed using a new high-resolution technique based on X-ray magnetic circular dichroism (XMCD). Superconductors coated with thin soft magnetic layers of CoFeB are observed in a scanning x-ray microscope providing cooling of the sample down to 83 K under the influence of external magnetic fields. Resulting electrical currents create an inhomogeneous magnetic field distribution above the superconductor which leads to a local reorientation of the ferromagnetic layer. X-ray absorption measurements with circular polarized radiation allows the analysis of the magnetic flux distribution in the superconductor via the ferromagnetic layer. In this work we present first images taken at 83K with high spatial resolution in the nanoscale.

  4. Elemental and Chemical Mapping of High Capacity Intermetallic Li-ion Anodes with Transmission X-ray Microscopy

    Science.gov (United States)

    Ausderau, Logan J.; Gonzalez Malabet, Hernando J.; Buckley, Joseph R.; De Andrade, Vincent; Liu, Yijin; Nelson, George J.

    2017-09-01

    X-ray nanotomography has been applied toward the three-dimensional (3D) imaging of a Li-ion battery alloy anode material (Cu6Sn5), and subsequent segmentation and analysis has been performed to distinguish the alloy material from its constituent components. Follow-on x-ray absorption near edge structure imaging was performed yielding absorption spectra for Cu, Cu6Sn5, and Li2CuSn. Analyses based on these spectra were performed on two-dimensional (2D) images of samples from cycled electrodes to assess chemical composition in Cu-containing phases. The capability to distinguish the different materials within mixed samples suggests that microstructure and composition changes resulting from lithiation and delithiation in Cu6Sn5 may be observed and better understood with 3D x-ray imaging methods. These methods are expected to be applicable to other intermetallic tin alloy electrodes.

  5. Biomedical applications of X-ray absorption and vibrational spectroscopic microscopies in obtaining structural information from complex systems

    Science.gov (United States)

    Aitken, Jade B.; Carter, Elizabeth A.; Eastgate, Harold; Hackett, Mark J.; Harris, Hugh H.; Levina, Aviva; Lee, Yao-Chang; Chen, Ching-Iue; Lai, Barry; Vogt, Stefan; Lay, Peter A.

    2010-02-01

    Protein crystallography and NMR spectroscopy took decades to emerge as routine techniques in structural biology. X-ray absorption spectroscopy now has reached a similar stage of maturity for obtaining complementary local structural information around metals in metalloproteins. However, the relatively recent emergence of X-ray and vibrational spectroscopic microprobes that build on these techniques has enabled the structural information obtained from the "mature" techniques on isolated biomolecules to be translated into in situ structural information from inhomogeneous complex systems, such as whole cells and tissues.

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

    Science.gov (United States)

    Benzerara, Karim; Menguy, Nicolas; Obst, Martin; Stolarski, Jarosław; Mazur, Maciej; Tylisczak, Tolek; Brown, Gordon E; Meibom, Anders

    2011-07-01

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

  7. 3D chemical mapping: application of scanning transmission (soft) X-ray microscopy (STXM) in combination with angle-scan tomography in bio-, geo-, and environmental sciences.

    Science.gov (United States)

    Obst, Martin; Schmid, Gregor

    2014-01-01

    The identification of environmental processes and mechanisms often requires information on the organochemical and inorganic composition of specimens at high spatial resolution. X-ray spectroscopy (XAS) performed in the soft X-ray range (100-2,200 eV) provides chemical speciation information for elements that are of high biogeochemical relevance such as carbon, nitrogen, and oxygen but also includes transition metals such as iron, manganese, or nickel. Synchrotron-based scanning transmission X-ray microscopy (STXM) combines XAS with high resolution mapping on the 20-nm scale. This provides two-dimensional (2D) quantitative information about the distribution of chemical species such as organic macromolecules, metals, or mineral phases within environmental samples. Furthermore, the combination of STXM with angle-scan tomography allows for three-dimensional (3D) spectromicroscopic analysis of bio-, geo-, or environmental samples. For the acquisition of STXM tomography data, the sample is rotated around an axis perpendicular to the X-ray beam. Various sample preparation approaches such as stripes cut from TEM grids or the preparation of wet cells allow for preparing environmentally relevant specimens in a dry or in a fully hydrated state for 2D and 3D STXM measurements. In this chapter we give a short overview about the principles of STXM, its application to environmental sciences, different preparation techniques, and the analysis and 3D reconstruction of STXM tomography data.

  8. Faradaurate-940: synthesis, mass spectrometry, electron microscopy, high-energy X-ray diffraction, and X-ray scattering study of Au∼940±20(SR)∼160±4 nanocrystals.

    Science.gov (United States)

    Kumara, Chanaka; Zuo, Xiaobing; Cullen, David A; Dass, Amala

    2014-06-24

    Obtaining monodisperse nanocrystals and determining their composition to the atomic level and their atomic structure is highly desirable but is generally lacking. Here, we report the discovery and comprehensive characterization of a 2.9 nm plasmonic nanocrystal with a composition of Au940±20(SCH2CH2Ph)160±4, which is the largest mass spectrometrically characterized gold thiolate nanoparticle produced to date. The compositional assignment has been made using electrospray ionization and matrix-assisted laser desorption ionization mass spectrometry (MS). The MS results show an unprecedented size monodispersity, where the number of Au atoms varies by only 40 atoms (940 ± 20). The mass spectrometrically determined composition and size are supported by aberration-corrected scanning transmission electron microscopy (STEM) and synchrotron-based methods such as atomic pair distribution function (PDF) and small-angle X-ray scattering (SAXS). Lower-resolution STEM images show an ensemble of particles-1000s per frame-visually demonstrating monodispersity. Modeling of SAXS data on statistically significant nanoparticle population-approximately 10(12) individual nanoparticles-shows that the diameter is 3.0 ± 0.2 nm, supporting mass spectrometry and electron microscopy results on monodispersity. Atomic PDF based on high-energy X-ray diffraction experiments shows decent match with either a Marks decahedral or truncated octahedral structure. Atomic resolution STEM images of single particles and their fast Fourier transform suggest face-centered cubic arrangement. UV-visible spectroscopy data show that Faradaurate-940 supports a surface plasmon resonance peak at ̃505 nm. These monodisperse plasmonic nanoparticles minimize averaging effects and have potential application in solar cells, nano-optical devices, catalysis, and drug delivery.

  9. Skull x-ray

    Science.gov (United States)

    X-ray - head; X-ray - skull; Skull radiography; Head x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

  10. Neck x-ray

    Science.gov (United States)

    X-ray - neck; Cervical spine x-ray; Lateral neck x-ray ... There is low radiation exposure. X-rays are monitored so that the lowest amount of radiation is used to produce the image. Pregnant women and ...

  11. Combined Application of QEM-SEM and Hard X-ray Microscopy to Determine Mineralogical Associations and Chemcial Speciation of Trace Metals

    Energy Technology Data Exchange (ETDEWEB)

    M Grafe; M Landers; R Tappero; P Austin; B Gan; A Grabsch; C Klauber

    2011-12-31

    We describe the application of quantitative evaluation of mineralogy by scanning electron microscopy in combination with techniques commonly available at hard X-ray microprobes to define the mineralogical environment of a bauxite residue core segment with the more specific aim of determining the speciation of trace metals (e.g., Ti, V, Cr, and Mn) within the mineral matrix. Successful trace metal speciation in heterogeneous matrices, such as those encountered in soils or mineral residues, relies on a combination of techniques including spectroscopy, microscopy, diffraction, and wet chemical and physical experiments. Of substantial interest is the ability to define the mineralogy of a sample to infer redox behavior, pH buffering, and mineral-water interfaces that are likely to interact with trace metals through adsorption, coprecipitation, dissolution, or electron transfer reactions. Quantitative evaluation of mineralogy by scanning electron microscopy coupled with micro-focused X-ray diffraction, micro-X-ray fluorescence, and micro-X-ray absorption near edge structure (mXANES) spectroscopy provided detailed insights into the composition of mineral assemblages and their effect on trace metal speciation during this investigation. In the sample investigated, titanium occurs as poorly ordered ilmenite, as rutile, and is substituted in iron oxides. Manganese's spatial correlation to Ti is closely linked to ilmenite, where it appears to substitute for Fe and Ti in the ilmenite structure based on its mXANES signature. Vanadium is associated with ilmenite and goethite but always assumes the +4 oxidation state, whereas chromium is predominantly in the +3 oxidation state and solely associated with iron oxides (goethite and hematite) and appears to substitute for Fe in the goethite structure.

  12. 软X射线显微术和光谱显微术%Microscopy and spectromicroscopy with soft X-ray

    Institute of Scientific and Technical Information of China (English)

    J Thieme; S Gleber; G Mitrea; P Guttmann

    2007-01-01

    X-ray microscopy is capable of imaging particles in the colloidal size range directly in their aqueous environment with high spatial resolution.It is possible to combine this with high spectral resolution for spectromicroscopic studies.Two types of microscopes are common in X-ray microscopy,the transmission X-ray microscope and the scanning transmission X-ray microscope,whose setup is shown in this paper.While an X-ray microscope quickly takes high resolution images from an object,a scanning X-ray microscope as an analytical instrument is suited for spectromicroscopy.As an example for visualization of morphology,clay and soil samples have been imaged with a transmission X-ray microscope.Images from a cryotomography experiment based on X-ray microscopy images to obtain information about the 3D structure of microhabitats formed by bacteria and other soil colloids are shown.The analysis of a stack of images taken with a scanning transmission X-ray microscope to bring together morphology and chemistry within a soil sample is given.%X射线显微术可直接在水环境中对胶体颗粒尺寸范围内的颗粒进行高分辨率成像,将该项技术与高分辨率光谱相结合,还可用于光谱显微研究.其中,常用的两种X射线显微镜是透射显微镜和扫描透射显微镜,文中示出了它们的装置图.由于X射线显微镜能迅速拍下一物体的高分辨率图像,所以,作为一种分析仪器,扫描X射线显微镜更适合作光谱显微研究.作为形态学目视化的一个示例,本文用一台透射X射线显微镜拍摄了粘土和土壤样品的图像.根据X射线图像进行的低温层析实验所获得的图像得到了有关细菌构成的显微生存环境以及其它土壤胶状体的3D结构信息.对扫描透射X射线显微镜拍摄的一系列图像进行分析,得到了土壤样品的形貌特性和化学特性.

  13. Quantitative characterization of the protein contents of the exocrine pancreatic acinar cell by soft x-ray microscopy and advanced digital imaging methods

    Energy Technology Data Exchange (ETDEWEB)

    Loo Jr., Billy W.

    2000-06-09

    The study of the exocrine pancreatic acinar cell has been central to the development of models of many cellular processes, especially of protein transport and secretion. Traditional methods used to examine this system have provided a wealth of qualitative information from which mechanistic models have been inferred. However they have lacked the ability to make quantitative measurements, particularly of the distribution of protein in the cell, information critical for grounding of models in terms of magnitude and relative significance. This dissertation describes the development and application of new tools that were used to measure the protein content of the major intracellular compartments in the acinar cell, particularly the zymogen granule. Soft x-ray microscopy permits image formation with high resolution and contrast determined by the underlying protein content of tissue rather than staining avidity. A sample preparation method compatible with x-ray microscopy was developed and its properties evaluated. Automatic computerized methods were developed to acquire, calibrate, and analyze large volumes of x-ray microscopic images of exocrine pancreatic tissue sections. Statistics were compiled on the protein density of several organelles, and on the protein density, size, and spatial distribution of tens of thousands of zymogen granules. The results of these measurements, and how they compare to predictions of different models of protein transport, are discussed.

  14. Quantitative characterization of the protein contents of the exocrine pancreatic acinar cell by soft x-ray microscopy and advanced digital imaging methods

    Energy Technology Data Exchange (ETDEWEB)

    Loo, Jr., Billy W. [Univ. of California, Berkeley, CA (United States)

    2000-06-01

    The study of the exocrine pancreatic acinar cell has been central to the development of models of many cellular processes, especially of protein transport and secretion. Traditional methods used to examine this system have provided a wealth of qualitative information from which mechanistic models have been inferred. However they have lacked the ability to make quantitative measurements, particularly of the distribution of protein in the cell, information critical for grounding of models in terms of magnitude and relative significance. This dissertation describes the development and application of new tools that were used to measure the protein content of the major intracellular compartments in the acinar cell, particularly the zymogen granule. Soft x-ray microscopy permits image formation with high resolution and contrast determined by the underlying protein content of tissue rather than staining avidity. A sample preparation method compatible with x-ray microscopy was developed and its properties evaluated. Automatic computerized methods were developed to acquire, calibrate, and analyze large volumes of x-ray microscopic images of exocrine pancreatic tissue sections. Statistics were compiled on the protein density of several organelles, and on the protein density, size, and spatial distribution of tens of thousands of zymogen granules. The results of these measurements, and how they compare to predictions of different models of protein transport, are discussed.

  15. Cryogenic coherent X-ray diffraction imaging of biological samples at SACLA: a correlative approach with cryo-electron and light microscopy.

    Science.gov (United States)

    Takayama, Yuki; Yonekura, Koji

    2016-03-01

    Coherent X-ray diffraction imaging at cryogenic temperature (cryo-CXDI) allows the analysis of internal structures of unstained, non-crystalline, whole biological samples in micrometre to sub-micrometre dimensions. Targets include cells and cell organelles. This approach involves preparing frozen-hydrated samples under controlled humidity, transferring the samples to a cryo-stage inside a vacuum chamber of a diffractometer, and then exposing the samples to coherent X-rays. Since 2012, cryo-coherent diffraction imaging (CDI) experiments have been carried out with the X-ray free-electron laser (XFEL) at the SPring-8 Ångstrom Compact free-electron LAser (SACLA) facility in Japan. Complementary use of cryo-electron microscopy and/or light microscopy is highly beneficial for both pre-checking samples and studying the integrity or nature of the sample. This article reports the authors' experience in cryo-XFEL-CDI of biological cells and organelles at SACLA, and describes an attempt towards reliable and higher-resolution reconstructions, including signal enhancement with strong scatterers and Patterson-search phasing.

  16. Growth and structure of water on SiO2 films on Si investigated byKelvin probe microscopy and in situ X-ray Spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Verdaguer, A.; Weis, C.; Oncins, G.; Ketteler, G.; Bluhm, H.; Salmeron, M.

    2007-06-14

    The growth of water on thin SiO{sub 2} films on Si wafers at vapor pressures between 1.5 and 4 torr and temperatures between -10 and 21 C has been studied in situ using Kelvin Probe Microscopy and X-ray photoemission and absorption spectroscopies. From 0 to 75% relative humidity (RH) water adsorbs forming a uniform film 4-5 layers thick. The surface potential increases in that RH range by about 400 mV and remains constant upon further increase of the RH. Above 75% RH the water film grows rapidly, reaching 6-7 monolayers at around 90% RH and forming a macroscopic drop near 100%. The O K-edge near-edge X-ray absorption spectrum around 75% RH is similar to that of liquid water (imperfect H-bonding coordination) at temperatures above 0 C and ice-like below 0 C.

  17. Strain and lattice orientation distribution in SiN/Ge complementary metal–oxide–semiconductor compatible light emitting microstructures by quick x-ray nano-diffraction microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chahine, G. A.; Schülli, T. U. [European Synchrotron ESRF, Grenoble 38043 (France); Zoellner, M. H.; Guha, S.; Reich, C.; Zaumseil, P.; Capellini, G. [IHP-Leibniz Institute for Innovative Microelectronics, Frankfurt (Germany); Richard, M.-I. [European Synchrotron ESRF, Grenoble 38043 (France); Aix-Marseille Université, CNRS, IM2NP UMR 7334, Marseille 13397 (France); Schroeder, T. [IHP-Leibniz Institute for Innovative Microelectronics, Frankfurt (Germany); Institute of Physics and Chemistry, Brandenburg Technical University, Cottbus 03046 (Germany)

    2015-02-16

    This paper presents a study of the spatial distribution of strain and lattice orientation in CMOS-fabricated strained Ge microstripes using high resolution x-ray micro-diffraction. The recently developed model-free characterization tool, based on a quick scanning x-ray diffraction microscopy technique can image strain down to levels of 10{sup −5} (Δa/a) with a spatial resolution of ∼0.5 μm. Strain and lattice tilt are extracted using the strain and orientation calculation software package X-SOCS. The obtained results are compared with the biaxial strain distribution obtained by lattice parameter-sensitive μ-Raman and μ-photoluminescence measurements. The experimental data are interpreted with the help of finite element modeling of the strain relaxation dynamics in the investigated structures.

  18. [Investigation of characteristic microstructures of adhesive interface in wood/bamboo composite material by synchrotron radiation X-ray phase contrast microscopy].

    Science.gov (United States)

    Peng, Guan-Yun; Wang, Yu-Rong; Ren, Hai-Qing; Yang, Shu-Min; Ma, Hong-Xia; Xie, Hong-Lan; Deng, Biao; Du, Guo-Hao; Xiao, Ti-Qiao

    2013-03-01

    Third-generation synchrotron radiation X-ray phase-contrast microscopy(XPCM)can be used for obtaining image with edge enhancement, and achieve the high contrast imaging of low-Z materials with the spatial coherence peculiarity of X-rays. In the present paper, the characteristic microstructures of adhesive at the interface and their penetration in wood/bamboo composite material were investigated systematically by XPCM at Shanghai Synchrotron Radiation Facility (SSRF). And the effect of several processing techniques was analyzed for the adhesive penetration in wood/bamboo materials. The results show that the synchrotron radiation XPCM is expected to be one of the important precision detection methods for wood-based panels.

  19. Novel application of X-ray fluorescence microscopy (XFM) for the non-destructive micro-elemental analysis of natural mineral pigments on Aboriginal Australian objects.

    Science.gov (United States)

    Popelka-Filcoff, Rachel S; Lenehan, Claire E; Lombi, Enzo; Donner, Erica; Howard, Daryl L; de Jonge, Martin D; Paterson, David; Walshe, Keryn; Pring, Allan

    2016-06-07

    This manuscript presents the first non-destructive synchrotron micro-X-ray fluorescence study of natural mineral pigments on Aboriginal Australian objects. Our results demonstrate the advantage of XFM (X-ray fluorescence microscopy) of Aboriginal Australian objects for optimum sensitivity, elemental analysis, micron-resolution mapping of pigment areas and the method also has the advantage of being non-destructive to the cultural heritage objects. Estimates of pigment thickness can be calculated. In addition, based on the elemental maps of the pigments, further conclusions can be drawn on the composition and mixtures and uses of natural mineral pigments and whether the objects were made using traditional or modern methods and materials. This manuscript highlights the results of this first application of XFM to investigate complex mineral pigments used on Aboriginal Australian objects.

  20. X-ray reflectivity and atomic force microscopy studies of MOCVD grown AlxGa1-xN/GaN superlattice structures*

    Institute of Scientific and Technical Information of China (English)

    Wang Yuanzhang; Li Jinchai; Li Shuping; Chen Hangyang; Liu Dayi; Kang Junyong

    2011-01-01

    The grazing incidence X-ray reflectivity (GIXR) technique and atomic force microscopy (AFM) were exploited to obtain an accurate evaluation of the surfaces and interfaces for metalorganic chemical vapor deposition grown AlxGa1-xN/GaN superlattice structures. The X-ray diffraction results have been combined with reflectivity data to evaluate the layer thickness and Al mole fraction in the AlGaN layer. The presence ora smooth interface is responsible for the observation of intensity oscillation in GIXR, which is well correlated to step flow observation in AFM images of the surface. The structure with a low Al mole fraction (x = 0.25) and thin well width has a rather smooth surface for the Rrms of AFM data value is 0.45 nm.

  1. Table-top water window transmission x-ray microscopy: Review of the key issues, and conceptual design of an instrument for biology

    Science.gov (United States)

    Adam, Jean-François; Moy, Jean-Pierre; Susini, Jean

    2005-09-01

    As it has been beautifully demonstrated in synchrotron facilities, water window transmission x-ray microscopy (WW-TXM) has a great potential for high resolution three dimensional (3D) tomographic imaging of frozen cells, without the cumbersome staining and slicing preparation needed by electron microscopy. However, the existing instruments do not exactly meet the expectations of cell biologists in terms of performance and accessibility: 3D images of entire cells grown on a flat substrate with details in the 50-80nm range are necessary for structural cell studies. Functional imaging is also a key issue. Specific molecular probes are widely used to achieve molecular imaging in optical and electron microscopy. The same demand applies to x-ray microscopy. Immediate availability of the observation technique within the biology laboratory is as important as its performance. Therefore, WW-TXM will develop on a wider scale only when table-top instruments become available. We present a detailed analysis of such a microscope. The source is clearly the key element. Laser created plasmas of carbon or nitrogen are a proven but expensive solution. Cerenkov emission in vanadium has been demonstrated as a potential monochromatic source, but we emphasize severe obstacles: huge thermal load and radiation protection. We show that oxygenKα line excitation by an electron beam is a realistic alternative. Being a purely monochromatic source, it would allow the use of a high efficiency mirror condenser, while laser plasmas imply spectral selection with the associated losses. We then describe the main elements of an affordable laboratory microscope, supported by numerical simulations and preliminary experimental work. We also show that functionalized quantum dots, currently used in fluorescence microscopy, are equally detectable with soft x-rays and would allow a dual modality observation. Finally, the expected performance of this prototype is discussed and confronted by the requirements

  2. Synchrotron X-ray fluorescence microscopy of gallium in bladder tissue following gallium maltolate administration during urinary tract infection.

    Science.gov (United States)

    Ball, Katherine R; Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L; Blyth, Robert I R; Sham, Tsun-Kong; Dowling, Patricia M; Thompson, Julie

    2013-11-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived at the transitional epithelium, a potential site of uropathogenic E. coli infection. Gallium and iron were similarly but not identically distributed in the tissues, suggesting that at least some distribution mechanisms are not common between the two elements. The results of this study indicate that gallium maltolate may be a suitable candidate for further development as a novel antimicrobial therapy for urinary tract infections caused by uropathogenic E. coli.

  3. Synchrotron X-Ray Fluorescence Microscopy of Gallium in Bladder Tissue following Gallium Maltolate Administration during Urinary Tract Infection

    Science.gov (United States)

    Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L.; Blyth, Robert I. R.; Sham, Tsun-Kong; Dowling, Patricia M.; Thompson, Julie

    2013-01-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived at the transitional epithelium, a potential site of uropathogenic E. coli infection. Gallium and iron were similarly but not identically distributed in the tissues, suggesting that at least some distribution mechanisms are not common between the two elements. The results of this study indicate that gallium maltolate may be a suitable candidate for further development as a novel antimicrobial therapy for urinary tract infections caused by uropathogenic E. coli. PMID:23877680

  4. STXM goes 3D: digital reconstruction of focal stacks as novel approach towards confocal soft x-ray microscopy.

    Science.gov (United States)

    Späth, Andreas; Scho Ll, Simon; Riess, Christian; Schmidtel, Daniel; Paradossi, Gaio; Raabe, Jo Rg; Hornegger, Joachim; Fink, Rainer H

    2014-09-01

    Fresnel zone plate based soft x-ray transmission microspectroscopy has developed into a routine technique for high-resolution elemental or chemical 2D imaging of thin film specimens. The availability of high resolution Fresnel lenses with short depth of focus offers the possibility of optical slicing (in the third dimension) by focus series with resolutions in the submicron regime. We introduce a 3D reconstruction algorithm that uses a variance-based metric to assign a focus measure as basis for volume rendering. The algorithm is applied to simulated geometries and opaque soft matter specimens thus enabling 3D visualization. These studies with z-resolution of few 100nm serve as important step towards the vision of a confocal transmission x-ray microscope.

  5. A Scanning Transmission X-ray Microscopy Study of Cubic and Orthorhombic C3A and Their Hydration Products in the Presence of Gypsum

    Directory of Open Access Journals (Sweden)

    Vanessa Rheinheimer

    2016-08-01

    Full Text Available This paper shows the microstructural differences and phase characterization of pure phases and hydrated products of the cubic and orthorhombic (Na-doped polymorphs of tricalcium aluminate (C3A, which are commonly found in traditional Portland cements. Pure, anhydrous samples were characterized using scanning transmission X-ray microscopy (STXM, X-ray photoelectron spectroscopy (XPS and X-ray diffraction (XRD and demonstrated differences in the chemical and mineralogical composition as well as the morphology on a micro/nano-scale. C3A/gypsum blends with mass ratios of 0.2 and 1.9 were hydrated using a water/C3A ratio of 1.2, and the products obtained after three days were assessed using STXM. The hydration process and subsequent formation of calcium sulfate in the C3A/gypsum systems were identified through the changes in the LIII edge fine structure for Calcium. The results also show greater Ca LII binding energies between hydrated samples with different gypsum contents. Conversely, the hydrated samples from the cubic and orthorhombic C3A at the same amount of gypsum exhibited strong morphological differences but similar chemical environments.

  6. Development of wavelength-dispersive soft X-ray emission spectrometers for transmission electron microscopes--an introduction of valence electron spectroscopy for transmission electron microscopy.

    Science.gov (United States)

    Terauchi, Masami; Koike, Masato; Fukushima, Kurio; Kimura, Atsushi

    2010-01-01

    Two types of wavelength-dispersive soft X-ray spectrometers, a high-dispersion type and a conventional one, for transmission electron microscopes were constructed. Those spectrometers were used to study the electronic states of valence electrons (bonding electrons). Both spectrometers extended the acceptable energy regions to higher than 2000 eV. The best energy resolution of 0.08 eV was obtained for an Al L-emission spectrum by using the high-dispersion type spectrometer. By using the spectrometer, C K-emission of carbon allotropes, Cu L-emission of Cu(1-x)Zn(x) alloys and Pt M-emission spectra were presented. The FWHM value of 12 eV was obtained for the Pt Malpha-emission peak. The performance of the conventional one was also presented for ZnS and a section specimen of a multilayer device. W-M and Si-K emissions were clearly resolved. Soft X-ray emission spectroscopy based on transmission electron microscopy (TEM) has an advantage for obtaining spectra from a single crystalline specimen with a defined crystal setting. As an example of anisotropic soft X-ray emission, C K-emission spectra of single crystalline graphite with different crystal settings were presented. From the spectra, density of states of pi- and sigma-bondings were separately derived. These results demonstrated a method to analyse the electronic states of valence electrons of materials in the nanometre scale based on TEM.

  7. The relationship between crystal growth and defect structure: a study of potassium hydrogen phthalate using x-ray topography and atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ester, G.R.; Price, R.; Halfpenny, P.J. [Department of Materials Science and Engineering, University of Bath, Bath (United Kingdom)

    1999-05-21

    An investigation of the defect structure of crystals of potassium hydrogen phthalate (KAP) and its relationship to the crystallization behaviour has been carried out using x-ray diffraction topography and atomic force microscopy (AFM). Crystals of KAP grown from aqueous solution were found to exhibit very low defect densities in the range 5 to 15 cm{sup -2} and remarkably low levels of strain. The character and distribution of the dominant growth dislocation types were determined using x-ray topography. The most significant features of the dislocation structure were a tendency for certain dislocation types to nucleate in pairs and at growth sector boundaries. X-ray topography revealed sectorial variations in solvent inclusions and the complementary use of AFM has shown the relationship of this to growth spiral anisotropy on the (010) face of KAP crystals. Changes in KAP crystal morphology have been observed which result from extreme variations in dislocation density, leading to either spiral growth or, in the case of dislocation-free growth sectors, a two-dimensional nucleation mechanism. The bending of dislocations from one growth sector to another and the tendency of dislocations in this material to nucleate in pairs are discussed in the context of size-dependent crystal growth rates. (author)

  8. The relationship between crystal growth and defect structure: a study of potassium hydrogen phthalate using x-ray topography and atomic force microscopy

    Science.gov (United States)

    Ester, G. R.; Price, R.; Halfpenny, P. J.

    1999-05-01

    An investigation of the defect structure of crystals of potassium hydrogen phthalate (KAP) and its relationship to the crystallization behaviour has been carried out using x-ray diffraction topography and atomic force microscopy (AFM). Crystals of KAP grown from aqueous solution were found to exhibit very low defect densities in the range 5 to 15 cm-2 and remarkably low levels of strain. The character and distribution of the dominant growth dislocation types were determined using x-ray topography. The most significant features of the dislocation structure were a tendency for certain dislocation types to nucleate in pairs and at growth sector boundaries. X-ray topography revealed sectorial variations in solvent inclusions and the complementary use of AFM has shown the relationship of this to growth spiral anisotropy on the (010) face of KAP crystals. Changes in KAP crystal morphology have been observed which result from extreme variations in dislocation density, leading to either spiral growth or, in the case of dislocation-free growth sectors, a two-dimensional nucleation mechanism. The bending of dislocations from one growth sector to another and the tendency of dislocations in this material to nucleate in pairs are discussed in the context of size-dependent crystal growth rates.

  9. Local study of fissure caries by Fourier transform infrared microscopy and X-ray diffraction using synchrotron radiation.

    Science.gov (United States)

    Seredin, Pavel; Kashkarov, Vladimir; Lukin, Anatoliy; Ippolitov, Yury; Julian, Robert; Doyle, Stephen

    2013-09-01

    Investigations of intact dental enamel as well as carious-affected human dental enamel were performed using infrared spectromicroscopy and X-ray diffraction applying synchrotron radiation. Caries of enamel was shown to be characterized by an increase in the number of deformation and valence vibrations for N-C-O, N-H and C=O bonds, a decrease of the crystallinity index, and by the absence of the preferable orientation of hydroxyapatite crystals within the affected enamel. This indicates the presence of destructive processes in the organic matrix of hard tooth tissues.

  10. 固定化青霉素G酰化酶活性的X射线微分析Ⅰ:捕捉剂的X射线能谱分析%Localization of activity of immobilized penicillin G acylase by X-ray microanalysis Ⅰ: Analysis of capture by EDS

    Institute of Scientific and Technical Information of China (English)

    姚子华; 黄永章; 仇满德

    2001-01-01

    To localize the activity of immobilized penicillin G acylase by X-ray microanalysis, we chosen carefully reagent capturing site of enzyme activity. Wh en the substrate was hydrolyzed by immobilized penicillin G acylase,hydrolysis pr oduct reacted with capture and formed precipitation which deposited on active si te of immobilized penicillin G acylase. The interference of carrier, substrate a nd immobilized penicillin G acylase with capture was eliminated. FeCl3 was sel ec ted as capture of locating the active site of immobilized penicillin G acylase b y X-ray microanalysis.%筛选了能捕捉固定化青霉素G酰化酶活性部位的捕捉剂;底物经固定化青霉素G酰化酶 水解,捕捉剂与水解产物反应生成沉淀,沉积在固定化青霉素G酰化酶的催化活性部位。排除 了载体、底物、固定化青霉素G酰化酶对捕捉剂的干扰,FeCl3能用于固定化青霉素G酰化酶 X射线微区活性定位的捕捉剂。

  11. In situ characterization of delamination and crack growth of a CGO–LSM multi-layer ceramic sample investigated by X-ray tomographic microscopy

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Esposito, Vincenzo; Lauridsen, Erik Mejdal;

    2014-01-01

    The densification, delamination and crack growth behavior in a Ce0.9Gd0.1O1.95 (CGO) and (La0.85Sr0.15)0.9MnO3 (LSM) multi-layer ceramic sample was studied using in situ X-ray tomographic microscopy (microtomography) to investigate the critical dynamics of crack propagation and delamination...... in a multilayered sample. Naturally occurring defects, caused by the sample preparation process, are shown not to be critical in sample degradation. Instead defects are nucleated during the debinding step. Crack growth is significantly faster along the material layers than perpendicular to them, and crack growth...

  12. Plasma characterization of the gas-puff target source dedicated for soft X-ray microscopy using SiC detectors

    Directory of Open Access Journals (Sweden)

    Torrisi Alfio

    2016-06-01

    Full Text Available An Nd:YAG pulsed laser was employed to irradiate a nitrogen gas-puff target. The interaction gives rise to the emission of soft X-ray (SXR radiation in the ‘water window’ spectral range (λ= 2.3÷4.4 nm. This source was already successfully employed to perform the SXR microscopy. In this work, a Silicon Carbide (SiC detector was used to characterize the nitrogen plasma emission in terms of gas-puff target parameters. The measurements show applicability of SiC detectors for SXR plasma characterization.

  13. Structure determination of the indium induced Si(001)-(4X3) reconstruction by surface x-ray diffraction and scanning tunneling microscopy

    DEFF Research Database (Denmark)

    Bunk, O.; Falkenberg, G.; Seehofer, L.;

    1998-01-01

    The indium-induced Si(001)-(4 X 3) reconstruction has been investigated by surface X-ray diffraction (SXRD) measurements with synchrotron radiation and scanning tunneling microscopy (STM). The Patterson function analysis enables us to exclude In dimers as a structural element in this reconstruction....... We present a new structural model which includes 6 In atoms threefold coordinated to Si atoms and 5 displaced Si atoms per unit cell. Relaxations down to the sixth layer were determined. 'Trimers' made up of In-Si-In atoms are a key structural element. (C) 1998 Elsevier Science B.V....

  14. Observation of coupled vortex gyrations by 70-ps-time and 20-nm-space- resolved full-field magnetic transmission soft x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hyunsung; Yu, Young-Sang; Lee, Ki-Suk; Im, Mi-Young; Fischer, Peter; Bocklage, Lars; Vogel, Andreas; Bolte, Markus; Meier, Guido; Kim, Sang-Koog

    2010-09-01

    We employed time-and space-resolved full-field magnetic transmission soft x-ray microscopy to observe vortex-core gyrations in a pair of dipolar-coupled vortex-state Permalloy (Ni{sub 80}Fe{sub 20}) disks. The 70 ps temporal and 20 nm spatial resolution of the microscope enabled us to simultaneously measure vortex gyrations in both disks and to resolve the phases and amplitudes of both vortex-core positions. We observed their correlation for a specific vortex-state configuration. This work provides a robust and direct method of studying vortex gyrations in dipolar-coupled vortex oscillators.

  15. Ferroelectric domains in epitaxial PbxSr1−xTiO3 thin films investigated using X-ray diffraction and piezoresponse force microscopy

    Directory of Open Access Journals (Sweden)

    S. Fernandez-Peña

    2016-08-01

    Full Text Available We present a detailed study of compressively strained PbxSr1−xTiO3 thin films grown by off-axis radio frequency magnetron sputtering on (001-oriented Nb-doped SrTiO3 substrates. Film tetragonality and the ferroelectric critical temperatures are measured for samples of different composition and thickness and compared with a phenomenological Landau-Devonshire model. 180∘ ferroelectric domains are observed using both X-ray diffraction and piezoresponse force microscopy and domain sizes obtained by the two techniques are compared and discussed.

  16. X-ray photoelectron spectroscopy and atomic force microscopy characterization of the effects of etching Zn xCd 1- xTe surfaces

    Science.gov (United States)

    George, M. A.; Azoulay, M.; Jayatirtha, H. N.; Burger, A.; Collins, W. E.; Silberman, E.

    1993-10-01

    X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) was used for the first time to characterize the chemical composition of modified surfaces of Zn xCd 1- xTe single crystals. These surface treatments were selected for their relevance to device preparation procedures. The XPS peaks indicated an increase of the tellurium and a depletion of the cadmium concentrations upon etching in bromine methanol solution. AFM revealed the formation of pronounced Te inclusions. Higher x values correlated with a decrease in residual bromine left on the surface, while cut and polished samples had higher oxide concentrations and increased bromination of the surface than cleaved samples.

  17. Transmission Electron Microscopy and Scanning Transmission X-Ray Microscopy Studies on the Bioaccumulation and Tissue Level Absorption of TiO2 Nanoparticles in Daphnia magna.

    Science.gov (United States)

    Kwon, Dongwook; Nho, Hyun Woo; Yoon, Tae Hyun

    2015-06-01

    In this study, bioaccumulation and tissue-level absorption of TiO2 nanoparticles (NPs) in freshwater invertebrates were investigated using transmission electron microscopy (TEM) and scanning transmission X-ray microscopy (STXM). The TiO2 NPs were used to test impacts of core sizes (i.e., 5 ± 2 nm and 23 ± 7 nm for TiO2(SYN) and TiO2(P25), respectively) and agglomerations (i.e., well dispersed vs. highly agglomerated) on the uptake of TiO2 NPs in Daphnia magna (D. magna). Highly agglomerated TiO2 NPs, regardless of their core sizes, were heavily taken up into the digestive tract of D. magna and no detectable penetration of both TiO2 NPs into the gut epithelial cells of D. magna was observed in TEM and STXM images. However, significant damages involving morphological changes in the microvilli and gut epithelial cells (e.g., irregular shaped microvilli, epithelial cell protrusion, and dilatation of cytoplasmic inclusion) were observed only with the commercial TiO2 NPs (TiO2(P25)) with larger core size and mixed crystalline phase, while the laboratory synthesized TiO2 NPs (TiO2(Syn)) with smaller core size and single crystalline phase showed slight morphological changes in the gut microvilli and epithelial cells. In the case of D. magna exposed to the well dispersed synthetic TiO2 NP ((Cit)TiO2(Syn)), only a negligible amount of TiO2 NPs were found within the digestive tract of the D. magna without any significant damages in the gut microvilli and epithelial cells and any detectable penetrations of TiO2 NPs into epithelial cells of D. magna gut. These TEM and STXM observations confirmed us that uptake of NP into D. magna are strongly dependent on their agglomeration (i.e., hydrodynamic sizes), rather than their core sizes, while direct penetration of NPs into tissues of digestive tract seems unlikely without significant morphological changes (e.g., collapse of the epithelial tissue) caused by high toxicity of NPs or released metal ions.

  18. Chest X Ray?

    Science.gov (United States)

    ... this page from the NHLBI on Twitter. Chest X Ray A chest x ray is a fast and painless imaging test ... tissue scarring, called fibrosis. Doctors may use chest x rays to see how well certain treatments are ...

  19. X-Rays

    Science.gov (United States)

    X-rays are a type of radiation called electromagnetic waves. X-ray imaging creates pictures of the inside of ... different amounts of radiation. Calcium in bones absorbs x-rays the most, so bones look white. Fat ...

  20. Medical X-Rays

    Science.gov (United States)

    ... Benefits The discovery of X-rays and the invention of CT represented major advances in medicine. X- ... in X-ray and CT Examinations — X-ray definition, dose measurement, safety precautions, risk, and consideration with ...

  1. A microscope for hard x-rays based on parabolic compound refractive lenses

    Science.gov (United States)

    Schroer, C. G.; Lengeler, B.; Benner, B.; Günzler, F.; Tümmler, J.; Drakopoulos, M.; Weitkamp, T.; Snigirev, A.; Snigireva, I.

    2000-05-01

    We describe refractive x-ray lenses with parabolic profile that are genuine imaging devices, similar to glass lenses for visible light. They open considerable possibilities in x-ray microscopy, tomography, microanalysis, and coherent scattering. Based on these lenses a microscope for hard x-rays is described, that can operate in the range from 2 to 60 keV, allowing for magnifications up to 50. At present, using aluminum lenses, it is possible to image an area of about 300μm in diameter with a resolving power of 0.3μm. Using beryllium as a lens material, the resolution can be increased below 0.1μm. The microscope allows to image opaque samples without destructive sample preparation and without the need of a vacuum chamber. It is particularly useful for in situ studies of wet samples, like biological and geological specimens. Imaging in both absorption and phase contrast is possible.

  2. Implementation of X-ray fluorescence microscopy for investigation of elemental abnormalities in central nervous system tissue

    Energy Technology Data Exchange (ETDEWEB)

    Chwiej, J. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland)]. E-mail: jchwiej@novell.ftj.agh.edu.pl; Szczerbowska-Boruchowska, M. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Wojcik, S. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Lankosz, M. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Chlebda, M. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Adamek, D. [Institute of Neurology, Collegium Medicum, Jagiellonian University, ul. Botaniczna-3, 31-503 Cracow (Poland); Tomik, B. [Institute of Neurology, Collegium Medicum, Jagiellonian University, ul. Botaniczna-3, 31-503 Cracow (Poland); Setkowicz, Z. [Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, ul. Ingardena 6, 30-060 Cracow (Poland); Falkenberg, G. [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg (Germany); Stegowski, Z. [Faculty of Physics and Applied Computer Science, AGH, University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Szczudlik, A. [Institute of Neurology, Collegium Medicum, Jagiellonian University, ul. Botaniczna-3, 31-503 Cracow (Poland)

    2005-09-29

    The microbeam synchrotron radiation X-ray fluorescence technique (micro-SRXRF) was applied to topographic and quantitative elemental analysis of human spinal cord tissue sections. The feasibility of this technique for the determination of elemental abnormalities caused by neurodegenerative disorder, i.e. amyotrophic lateral sclerosis (ALS), was verified. The applied measurement conditions allowed detecting: P, S, Cl, K, Ca, Fe, Cu, Zn and Br in thin tissue slices. Two-dimensional maps of the elemental distribution were recorded. Quantitative differences in elemental concentration between gray matter, nerve cells and white matter were observed for all analyzed cases. For the motor neuron bodies higher accumulation of S, Cl, K, Fe, Zn and Br was noticed. The results showed significant differences of elemental accumulation between the analyzed ALS cases. Moreover, the feasibility of using tissue sections fixed and embedded in paraffin for micro-SRXRF analysis was tested. These studies were performed on the samples of rat brain.

  3. The interaction of asbestos and iron in lung tissue revealed by synchrotron-based scanning X-ray microscopy

    Science.gov (United States)

    Pascolo, Lorella; Gianoncelli, Alessandra; Schneider, Giulia; Salomé, Murielle; Schneider, Manuela; Calligaro, Carla; Kiskinova, Maya; Melato, Mauro; Rizzardi, Clara

    2013-01-01

    Asbestos is a potent carcinogen associated with malignant mesothelioma and lung cancer but its carcinogenic mechanisms are still poorly understood. Asbestos toxicity is ascribed to its particular physico-chemical characteristics, and one of them is the presence of and ability to adsorb iron, which may cause an alteration of iron homeostasis in the tissue. This observational study reports a combination of advanced synchrotron-based X-ray imaging and micro-spectroscopic methods that provide correlative morphological and chemical information for shedding light on iron mobilization features during asbestos permanence in lung tissue. The results show that the processes responsible for the unusual distribution of iron at different stages of interaction with the fibres also involve calcium, phosphorus and magnesium. It has been confirmed that the dominant iron form present in asbestos bodies is ferritin, while the concurrent presence of haematite suggests alteration of iron chemistry during asbestos body permanence. PMID:23350030

  4. Innovative analytical methodology combining micro-x-ray diffraction, scanning electron microscopy-based mineral maps, and diffuse reflectance infrared fourier transform spectroscopy to characterize archeological artifacts.

    Science.gov (United States)

    Cardell, Carolina; Guerra, Isabel; Romero-Pastor, Julia; Cultrone, Giuseppe; Rodriguez-Navarro, Alejandro

    2009-01-15

    Excavations at the 14th century Moorish rampart (Granada, Spain) unearthed a brick oven alongside black ash and bone stratigraphic layers. In situ evidence suggests the oven served to fabricate a wall coating including powdered burnt bones. Original ad hoc analyses improved on conventional methods were used to confirm this hypothesis. These methods enable (i) nondestructive micro-X-ray diffraction (mu-XRD) for fast mineralogical data acquisition (approximately 10 s) and moderately high spatial (approximately 500 microm) resolution and (ii) identification and imaging of crystalline components in sample cross-sections via mineral maps, yielding outstanding visualization of grain distribution and morphology in composite samples based on scanning electron microscopy-energy dispersion X-ray spectrometry (SEM-EDX) elemental maps. Benefits are shown for applying diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) vs transmittance-FT-IR (T-FT-IR) to analyze organic and inorganic components in single samples. Complementary techniques to fully characterize artifacts were gas chromatography/mass spectroscopy (GC/MS), optical microscopy (OM), conventional powder XRD, and (14)C dating. Bone-hydroxyapatite was detected in the coating. Mineralogical transformations in the bricks indicate oven temperatures well above 1000 degrees C, supporting the hypothesis.

  5. Investigation of biodistribution behavior of platinum particles in mice: Correlation between inductively coupled plasma-atomic emission spectroscopy and X-ray scanning analytical microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Shigeaki, E-mail: sabe@den.hokudai.ac.jp [Graduate School of Dental Medicine, Hokkaido University, Sapporo (Japan); Koyama, Chika; Mutoh, Mami [Faculty of Dental Medicine, Hokkaido University, Sapporo (Japan); Akasaka, Tsukasa [Graduate School of Dental Medicine, Hokkaido University, Sapporo (Japan); Uo, Motohiro [Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Watari, Fumio [Graduate School of Dental Medicine, Hokkaido University, Sapporo (Japan)

    2012-12-01

    Highlights: Black-Right-Pointing-Pointer We investigated the biodistribution of platinum microparticles in mice. Black-Right-Pointing-Pointer The biodistribution behavior was observed using inductively coupled plasma-atomic emission spectroscopy (ICP) and scanning X-ray analytical microscopy (XSAM). Black-Right-Pointing-Pointer The administered particles quickly reached in spleen, liver and lung with constant ration. Black-Right-Pointing-Pointer We also estimated the correlation ship between XSAM and ICP measurement. Black-Right-Pointing-Pointer The relative ratio of XSAM intensity showed highly correlation with the relative ratio of Pt concentration in organs. - Abstract: In this study, we investigated the biodistribution of platinum (Pt) microparticles in mice. The particles were administered through the tail vein, and then the biodistribution behavior was observed using inductively coupled plasma-atomic emission spectroscopy (ICP) and scanning X-ray analytical microscopy (XSAM). The administered particles quickly reached the spleen, liver, and lung at a constant ratio, and the ratio remained constant for four weeks. We also estimated the correlation between XSAM and ICP measurement. The relative ratio of XSAM intensity showed strong correlation with the relative ratio of Pt concentration in organs.

  6. Functional biocompatible magnetite-cellulose nanocomposite fibrous networks: Characterization by fourier transformed infrared spectroscopy, X-ray powder diffraction and field emission scanning electron microscopy analysis.

    Science.gov (United States)

    Habibi, Neda

    2015-02-05

    The preparation and characterization of functional biocompatible magnetite-cellulose nano-composite fibrous material is described. Magnetite-cellulose nano-composite was prepared by a combination of the solution-based formation of magnetic nano-particles and subsequent coating with amino celluloses. Characterization was accomplished using X-ray powder diffraction (XRD), fourier transformed infrared (FTIR) and field emission scanning electron microscopy (FESEM) analysis. The peaks of Fe3O4 in the XRD pattern of nanocomposite confirm existence of the nanoparticles in the amino cellulose matrix. Magnetite-cellulose particles exhibit an average diameter of roughly 33nm as demonstrated by field emission scanning electron microscopy. Magnetite nanoparticles were irregular spheres dispersed in the cellulose matrix. The vibration corresponding to the NCH3 functional group about 2850cm(-1) is assigned in the FTIR spectra. Functionalized magnetite-cellulose nano-composite polymers have a potential range of application as targeted drug delivery system in biomedical field.

  7. Analysis of InGaN nanodots grown by droplet heteroepitaxy using grazing incidence small-angle X-ray scattering and electron microscopy

    Science.gov (United States)

    Woodward, J. M.; Nikiforov, A. Yu.; Ludwig, K. F.; Moustakas, T. D.

    2017-08-01

    We present a detailed structural investigation of self-assembled indium gallium nitride nanodots grown on c-plane aluminum nitride templates by the droplet heteroepitaxy technique in a plasma-assisted molecular beam epitaxy reactor. Various growth parameters, including the total coverage of the metal species, relative and total metal effusion fluxes, and nitridation temperature were investigated. Analyses of in situ reflection high-energy electron diffraction patterns and comparison with simulations showed that the resulting crystal structure was a mixture of wurtzite and twinned zinc blende phases, with the zinc blende phase increasingly dominant for lower metal coverages and lower nitridation temperatures, and the wurtzite phase increasingly dominant for higher nitridation temperature. Studies by field emission scanning electron microscopy and atomic force microscopy revealed that the nanodots exhibit trimodal size distributions, with the dot morphologies of the intermediate size mode often resembling aggregations of distinct clusters. Nanodots grown at higher nitridation temperatures had larger inter-dot spacings, with hexagonal in-plane ordering observable at a sufficiently high temperature. Using grazing incidence small angle X-ray scattering, we determined the nanodots to be approximately truncated cone shaped, and extracted the mean radius, height, and inter-dot distance for each distribution. Microstructural investigations of the nanodots by cross-sectional transmission electron microscopy indicated that the majority of the dots were formed in dislocation-free regions, and confirmed that the intermediate size dots were approximately truncated cone shaped and consisted of both zinc blende and wurtzite regions. Mapping of the elemental distributions by energy dispersive X-ray spectroscopy in scanning transmission electron microscopy mode indicated highly nonuniform indium distributions within both small and intermediate size dots which are potentially

  8. 电子探针分析乳牙釉质和牙本质钙含量的研究%The study on deciduous teeth enamel and dentin calcium content analyzed by Electron Probe X-ray Microanalysis

    Institute of Scientific and Technical Information of China (English)

    刘芸; 石四箴

    2011-01-01

    Objective To study the calcium content and distribution of deciduous teeth enamel and dentine and to discuss its relationship with caries. Methods Using Electron Probe X-ray Microanalysis (EPMA) microanalyzer to measure the calcium content at different depths on the vertical section of 40 mandibular deciduous central incisors and then grouping according to caries status of individual sample, each group is analyzed statistically respectively. Results The average value of total calcium content for the 40 mandibular deciduous central incisors is 37.13 ± 1.10 (wt%), the calcium content of enamel is 38.31 ± 0.94 (wt%), the calcium content of dentine is 36.66 ± 1.38 (wt%); the calcium content of enamel subsurface 50|xm and 100u.ni is higher than enamel subsurface 250u,m; the calcium content of dentine under-enamelo-dentinal junction 50u,m and 100|xm is lower than respectively dentine under-enamelo-dentinal junction 450u,m, 500u,m, 550jxm and 600|xm. A statistics difference is not seen for the normal deciduous teeth's calcium content between caries-free group, low caries risk group and high caries risk group, and the normal deciduous teeth's calcium content has no correlation with decayed-filled tooth, decayed-filled surface and caries severity index. Conclusion The calcium distribution of normal deciduous teeth is non-homogeneous state. The calcium content of enamel showed a gradual decreasing trend from surface towards enamelo -dentinal junction; the calcium content of dentine showed a gradual increasing trend from enamelo-dentinal junction towards pulp cavity side. The calcium content of normal development deciduous teeth does not reflect the situation of individual caries as a single indicator.%目的 研究乳牙釉质和牙本质中钙含量及分布,探讨其与龋患状况之间的关系.方法 运用电子探针显微分析仪测定40颗离体下颌乳中切牙纵剖面上不同深度的钙含量,并以标本所在个体的龋患状况分组,分

  9. Imaging endosomes and autophagosomes in whole mammalian cells using correlative cryo-fluorescence and cryo-soft X-ray microscopy (cryo-CLXM)

    Energy Technology Data Exchange (ETDEWEB)

    Duke, Elizabeth M.H. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Razi, Minoo [Secretory Pathways Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Weston, Anne [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Guttmann, Peter; Werner, Stephan; Henzler, Katja; Schneider, Gerd [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institute for Soft Matter and Functional Materials, 12489 Berlin (Germany); Tooze, Sharon A. [Secretory Pathways Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Collinson, Lucy M., E-mail: lucy.collinson@cancer.org.uk [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom)

    2014-08-01

    Cryo-soft X-ray tomography (cryo-SXT) is a powerful imaging technique that can extract ultrastructural information from whole, unstained mammalian cells as close to the living state as possible. Subcellular organelles including the nucleus, the Golgi apparatus and mitochondria have been identified by morphology alone, due to the similarity in contrast to transmission electron micrographs. In this study, we used cryo-SXT to image endosomes and autophagosomes, organelles that are particularly susceptible to chemical fixation artefacts during sample preparation for electron microscopy. We used two approaches to identify these compartments. For early and recycling endosomes, which are accessible to externally-loaded markers, we used an anti-transferrin receptor antibody conjugated to 10 nm gold particles. For autophagosomes, which are not accessible to externally-applied markers, we developed a correlative cryo-fluorescence and cryo-SXT workflow (cryo-CLXM) to localise GFP-LC3 and RFP-Atg9. We used a stand-alone cryo-fluorescence stage in the home laboratory to localise the cloned fluorophores, followed by cryo-soft X-ray tomography at the synchrotron to analyse cellular ultrastructure. We mapped the 3D ultrastructure of the endocytic and autophagic structures, and discovered clusters of omegasomes arising from ‘hotspots’ on the ER. Thus, immunogold markers and cryo-CLXM can be used to analyse cellular processes that are inaccessible using other imaging modalities. - Highlights: • We image whole, unstained mammalian cells using cryo-soft X-ray tomography. • Endosomes are identified using a gold marker for the transferrin receptor. • A new workflow for correlative cryo-fluorescence and cryo-SXT is used to locate early autophagosomes. • Interactions between endosomes, endoplasmic reticulum and forming autophagosomes are mapped in 3D. • Multiple omegasomes are shown to form at ‘hotspots’ on the endoplasmic reticulum.

  10. Classification of Multiple Types of Organic Carbon Composition in Atmospheric Particles by Scanning Transmission X-Ray Microscopy Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kilcoyne, Arthur L; Takahama, S.; Gilardoni, S.; Russell, L.M.; Kilcoyne, A.L.D.

    2007-05-16

    A scanning transmission X-ray microscope at the Lawrence Berkeley National Laboratory is used to measure organic functional group abundance and morphology of atmospheric aerosols. We present a summary of spectra, sizes, and shapes observed in 595 particles that were collected and analyzed between 2000 and 2006. These particles ranged between 0.1 and 12 mm and represent aerosols found in a large range of geographical areas, altitudes, and times. They include samples from seven different field campaigns: PELTI, ACE-ASIA, DYCOMS II, Princeton, MILAGRO (urban), MILAGRO (C-130), and INTEX-B. At least 14 different classes of organic particles show different types of spectroscopic signatures. Different particle types are found within the same region while the same particle types are also found in different geographical domains. Particles chemically resembling black carbon, humic-like aerosols, pine ultisol, and secondary or processed aerosol have been identified from functional group abundance and comparison of spectra with those published in the literature.

  11. Molecular ordering in a biaxial smectic-A phase studied by scanning transmission X-ray microscopy (STXM).

    Science.gov (United States)

    Kaznacheev, Konstantin; Hegmann, Torsten

    2007-04-14

    Results of STXM investigations of a binary mixture (-TNF = 2 : 1; SmA(b) 140 M 180 Iso) known to form a SmA(b) phase [T. Hegmann, J. Kain, S. Diele, G. Pelzl and C. Tschierske, Angew. Chem. Int. Ed., 2001, 40, 887] are presented. Near edge X-ray absorption fine spectra (NEXAFS) of the -TNF board-like aggregates, in particular the intensity of the low energy peaks associated with aromatic ring pi* orbitals (284.5-286.5 eV), show that the molecular plane of these aggregates is very sensitive to the relative orientation of electric field vector E of linearly polarized light, which is used to determine the molecular orientation in the LC phase. The observed strong in-plane dichroic signal suggests the predominant orientation of the -TNF aggregates to be along the smectic layer normal as well as long-range ordering of the in-plane molecular orientation (biaxiality). Orientational maps derived from series of measurements at different sample rotation angles around the specimen normal clearly show a Schlieren-type texture, and permit a detailed examination of exclusive +/-(1/2) disclination theoretically predicted for the SmA(b) phase.

  12. EPS composition and calcification potential of tufa-dominating cyanobacteria investigated by Scanning Transmission X-ray Microscopy (STXM) and Laser Scanning Microscopy (LSM)

    Science.gov (United States)

    Zippel, Barbara; Dynes, James J.; Obst, Martin; Lawrence, John R.; Neu, Thomas R.

    2010-05-01

    Tufa deposits in freshwater habitats are the result of calcium carbonate precipitation within interfacial microbial ecosystems. Calcite precipitation is influenced by the saturation index and the occurrence of extracellular polymeric substances (EPS) which are produced by a variety of microorganisms. In theory, the first important step of biologically induced calcification processes is the adsorption of calcium ions by extracellular polymeric substances (EPS) produced by cyanobacteria. In the present study we take advantage of Laser Scanning Microscopy (LSM) and combine it with Synchrotron imaging using Scanning Transmission X-ray Microscopy (STXM). STXM represents a technique that allows simultaneous analysis of inorganic and organic constituents as a scale of 50 nm. By means of STXM it is possible to differentiate between calcium carbonate phases at the Ca L-edge. Furthermore, STXM has also been used at the C K-edge to map the major biomolecules (proteins, lipids, and polysaccharides). The purpose of this study is to find out if there are differences in calcium adsorption depending on specific composition of the EPS produced by filamentous cyanobacteria isolated from a German hard water creek (Westerhöfer Bach, Harz Mountains). The goal was to elucidate the potential of biofilms constituents, including microbial cell surfaces as well as extracellular polymeric substances, in triggering the formation of calcium carbonate in tufa systems. For this purpose three filamentous cyanobacteria (Pseudanabaena sp., Leptolyngbya sp. and Nostoc sp.) were cultivated in creek-adapted as well as standard media (BG11) on polycarbonate slides. In situ EPS composition was detected by means of fluorescence lectin-binding approach (FLBA) using 23 commercially available lectins with different specificities for mono- and disaccharides and amino sugars. For CaCO3 nucleation experiments cyanobacterial biofilms grown on polycarbonate slides were deposited in NaHCO3/CaCl2 solutions

  13. Synchrotron soft X-ray imaging and fluorescence microscopy reveal novel features of asbestos body morphology and composition in human lung tissues

    Directory of Open Access Journals (Sweden)

    Polentarutti Maurizio

    2011-02-01

    Full Text Available Abstract Background Occupational or environmental exposure to asbestos fibres is associated with pleural and parenchymal lung diseases. A histopathologic hallmark of exposure to asbestos is the presence in lung parenchyma of the so-called asbestos bodies. They are the final product of biomineralization processes resulting in deposition of endogenous iron and organic matter (mainly proteins around the inhaled asbestos fibres. For shedding light on the formation mechanisms of asbestos bodies it is of fundamental importance to characterize at the same length scales not only their structural morphology and chemical composition but also to correlate them to the possible alterations in the local composition of the surrounding tissues. Here we report the first correlative morphological and chemical characterization of untreated paraffinated histological lung tissue samples with asbestos bodies by means of soft X-ray imaging and X-Ray Fluorescence (XRF microscopy, which reveals new features in the elemental lateral distribution. Results The X-ray absorption and phase contrast images and the simultaneously monitored XRF maps of tissue samples have revealed the location, distribution and elemental composition of asbestos bodies and associated nanometric structures. The observed specific morphology and differences in the local Si, Fe, O and Mg content provide distinct fingerprints characteristic for the core asbestos fibre and the ferruginous body. The highest Si content is found in the asbestos fibre, while the shell and ferruginous bodies are characterized by strongly increased content of Mg, Fe and O compared to the adjacent tissue. The XRF and SEM-EDX analyses of the extracted asbestos bodies confirmed an enhanced Mg deposition in the organic asbestos coating. Conclusions The present report demonstrates the potential of the advanced synchrotron-based X-ray imaging and microspectroscopy techniques for studying the response of the lung tissue to the

  14. Examining the ground layer of St. Anthony from Padua 19th century oil painting by Raman spectroscopy, scanning electron microscopy and X-ray diffraction

    Science.gov (United States)

    Vančo, Ľubomír; Kadlečíková, Magdaléna; Breza, Juraj; Čaplovič, Ľubomír; Gregor, Miloš

    2013-01-01

    In this paper we studied the material composition of the ground layer of a neoclassical painting. We used Raman spectroscopy (RS) as a prime method. Thereafter scanning electron microscopy combined with energy dispersive spectroscopy (SEM-EDS) and X-ray powder diffraction (XRD) were employed as complementary techniques. The painting inspected was of the side altar in King St. Stephen's Church in Galanta (Slovakia), signed and dated by Jos. Chr. Mayer 1870. Analysis was carried out on both covered and uncovered ground layers. Four principal compounds (barite, lead white, calcite, dolomite) and two minor compounds (sphalerite, quartz) were identified. This ground composition is consistent with the 19th century painting technique used in Central Europe consisting of white pigments and white fillers. Transformation of lead white occurred under laser irradiation. Subdominant Raman peaks of the components were measured. The observed results elucidate useful partnership of RS and SEM-EDS measurements supported by X-ray powder diffraction as well as possibilities and limitations of non-destructive analysis of covered lower layers by RS.

  15. A simple method for detection of gunshot residue particles from hands, hair, face, and clothing using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX).

    Science.gov (United States)

    Kage, S; Kudo, K; Kaizoji, A; Ryumoto, J; Ikeda, H; Ikeda, N

    2001-07-01

    We devised a simple and rapid method for detection of gunshot residue (GSR) particles, using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX) analysis. Experiments were done on samples containing GSR particles obtained from hands, hair, face, and clothing, using double-sided adhesive coated aluminum stubs (tape-lift method). SEM/WDX analyses for GSR were carried out in three steps: the first step was map analysis for barium (Ba) to search for GSR particles from lead styphnate primed ammunition, or tin (Sn) to search for GSR particles from mercury fulminate primed ammunition. The second step was determination of the location of GSR particles by X-ray imaging of Ba or Sn at a magnification of x 1000-2000 in the SEM, using data of map analysis, and the third step was identification of GSR particles, using WDX spectrometers. Analysis of samples from each primer of a stub took about 3 h. Practical applications were shown for utility of this method.

  16. Multimodal nanoparticles as alignment and correlation markers in fluorescence/soft X-ray cryo-microscopy/tomography of nucleoplasmic reticulum and apoptosis in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, Christoph, E-mail: christoph@strubi.ox.ac.uk [Oxford Particle Imaging Centre, Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN (United Kingdom); Werner, Stephan, E-mail: stephan.werner@helmholtz-berlin.de [Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, 12489 Berlin (Germany); Carregal-Romero, Susana, E-mail: susana.carregal@physik.uni-marburg.de [Fachbereich Physik, Philipps Universität Marburg, Marburg 35043 (Germany); Malhas, Ashraf N., E-mail: ashraf.malhas@path.ox.ac.uk [Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE (United Kingdom); Klupp, Barbara G., E-mail: barbara.klupp@fli.bund.de [Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems (Germany); Guttmann, Peter, E-mail: peter.guttmann@helmholtz-berlin.de [Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, 12489 Berlin (Germany); Rehbein, Stefan, E-mail: stefan.rehbein@helmholtz-berlin.de [Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, 12489 Berlin (Germany); Henzler, Katja, E-mail: katja.henzler@helmholtz-berlin.de [Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, 12489 Berlin (Germany); Mettenleiter, Thomas C., E-mail: thomas.mettenleiter@fli.bund.de [Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems (Germany); and others

    2014-11-15

    Correlative fluorescence and soft X-ray cryo-microscopy/tomography on flat sample holders is perfectly suited to study the uncompromised physiological status of adherent cells at its best possible preservation by imaging after fast cryo-immobilization. To understand the mechanism by which herpesviruses induce nucleoplasmic reticulum, i.e. invaginations of the nuclear envelope, during their egress from the host cell nucleus, morphologically similar structures found in laminopathies and after chemical induction were investigated as a potentially more easily accessible model system. For example, anti-retroviral protease inhibitors like Saquinavir also induce invaginations of the nuclear membranes. With the help of newly designed multimodal nanoparticles as alignment and correlation markers, and by optimizing fluorescence cryo-microscopy data acquisition, an elaborate three-dimensional network of nucleoplasmic reticulum was demonstrated in nuclei of Saquinavir-treated rabbit kidney cells expressing a fluorescently labeled inner nuclear membrane protein. In part of the protease inhibitor-treated samples, nuclei exhibited dramatic ultrastructural changes indicative of programmed cell death/apoptosis. This unexpected observation highlights another unique feature of soft X-ray microscopy, i.e. high absorption contrast information not relying on labeled cellular components, at a 3D resolution of approximately 40 nm (half-pitch) and through a sample thickness of several micrometers. These properties make it a valuable part of the cell biology imaging toolbox to visualize the cellular ultrastructure in its completeness. - Highlights: • Nucleoplasmic reticulum was demonstrated in nuclei of Saquinavir-treated cells. • New polyelectrolyte-Qdot{sup ®} 605 coated gold beads were employed as fiducials. • Saquinavir can induce a strong apoptotic phenotype in the nucleus. • CryoXT is an auspicious imaging technique in apoptosis research.

  17. A comparative transmission electron microscopy, energy dispersive x-ray spectroscopy and spatially resolved micropillar compression study of the yttria partially stabilised zirconia - porcelain interface in dental prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Lunt, Alexander J.G., E-mail: alexander.lunt@chch.ox.ac.uk [Department of Engineering Science, University of Oxford, Parks Road, Oxford, Oxfordshire OX1 3PJ (United Kingdom); Mohanty, Gaurav, E-mail: gaurav.mohanty@empa.ch [EMPA Materials Science & Technology, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); Ying, Siqi, E-mail: siqi.ying@eng.ox.ac.uk [Department of Engineering Science, University of Oxford, Parks Road, Oxford, Oxfordshire OX1 3PJ (United Kingdom); Dluhoš, Jiří, E-mail: jiri.dluhos@tescan.cz [TESCAN Brno, s.r.o., Libušina tř. 1, 623 00 Brno-Kohoutovice (Czech Republic); Sui, Tan, E-mail: tan.sui@eng.ox.ac.uk [Department of Engineering Science, University of Oxford, Parks Road, Oxford, Oxfordshire OX1 3PJ (United Kingdom); Neo, Tee K., E-mail: neophyte@singnet.com.sg [Specialist Dental Group, Mount Elizabeth Orchard, 3 Mount Elizabeth, #08-03/08-08/08-10, 228510 (Singapore); Michler, Johann, E-mail: johann.michler@empa.ch [EMPA Materials Science & Technology, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); Korsunsky, Alexander M., E-mail: alexander.korsunsky@eng.ox.ac.uk [Department of Engineering Science, University of Oxford, Parks Road, Oxford, Oxfordshire OX1 3PJ (United Kingdom)

    2015-12-01

    Recent studies into the origins of failure of yttria partially stabilised zirconia–porcelain veneered prosthesis have revealed the importance of micro-to-nano scale characterisation of this interface zone. Current understanding suggests that the heat treatment, residual stresses and varying microstructure at this location may contribute to near-interface porcelain chipping. In this study the chemical, microstructural and mechanical property variation across the interfacial zone has been characterised at two differing length scales and using three independent techniques; energy dispersive X-ray spectroscopy, transmission electron microscopy and micropillar compression. Energy dispersive X-ray spectroscopy mapping of the near-interface region revealed, for the first time, that the diffusional lengths of twelve principal elements are limited to within 2–6 μm of the interface. This study also revealed that 0.2–2 μm diameter zirconia grains had become detached from the bulk and were embedded in the near-interface porcelain. Transmission electron microscopy analysis demonstrated the presence of nanoscale spherical features, indicative of tensile creep induced voiding, within the first 0.4–1.5 μm from the interface. Within zirconia, variations in grain size and atomistic structure were also observed within the 3 μm closest to the interface. Micropillar compression was performed over a 100 μm range on either side of the interface at the spatial resolution of 5 μm. This revealed an increase in zirconia and porcelain loading modulus at close proximities (< 5 μm) to the interface and a decrease in zirconia modulus at distances between 6 and 41 μm from this location. The combination of the three experimental techniques has revealed intricate details of the microstructural, chemical and consequently mechanical heterogeneities in the YPSZ–porcelain interface, and demonstrated that the length scales typically associated with this behaviour are approximately ± 5

  18. Mineral Compositions and Micro-Structural of Epoxy-Repaired Rock Revealed by X-ray Diffraction and Scanning Electron Microscopy

    Directory of Open Access Journals (Sweden)

    Wei Hu

    2013-09-01

    Full Text Available In order to improve the mechanical properties of rock with lots of cracks, this study adopts electronic methods (X-ray diffraction and scanning electron microscopy to determine the mineral compositions and micro structural characteristics of epoxy-repaired rock. Fractured rocks with low strength or high permeability may not be appropriate for dam foundation. The strength and durability of fractured rock are increased after chemical grouting. Test results show that, some of the cracks and voids are repaired by epoxy particles, resulted in the decreasing rock porosity. The proportion of epoxy resins is about 3.5%-5.5%, showing a discrete distribution and can not connect with each other.

  19. The Reactivity and Structural Dynamics of Supported Metal Nanoclusters Using Electron Microscopy, in situ X-Ray Spectroscopy, Electronic Structure Theories, and Molecular Dynamics Simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Judith C. Yang; Ralph G. Nuzzo, Duane Johnson, Anatoly Frenkel

    2008-07-01

    The distinguishing feature of our collaborative program of study is the focus it brings to emergent phenomena originating from the unique structural/electronic environments found in nanoscale materials. We exploit and develop frontier methods of atomic-scale materials characterization based on electron microscopy (Yang) and synchrotron X-ray absorption spectroscopy (Frenkel) that are in turn coupled innately with advanced first principles theory and methods of computational modeling (Johnson). In the past year we have made significant experimental advances that have led to important new understandings of the structural dynamics of what are unquestionably the most important classes of heterogeneous catalysts—the materials used to both produce and mitigate the consequences of the use of liquid hydrocarbon fuels.

  20. Characterising the structural properties of polymer separators for lithium-ion batteries in 3D using phase contrast X-ray microscopy

    Science.gov (United States)

    Finegan, Donal P.; Cooper, Samuel J.; Tjaden, Bernhard; Taiwo, Oluwadamilola O.; Gelb, Jeff; Hinds, Gareth; Brett, Dan J. L.; Shearing, Paul R.

    2016-11-01

    Separators are an integral component for optimising performance and safety of lithium-ion batteries; therefore, a clear understanding of how their microstructure affects cell performance and safety is crucial. Phase contrast X-ray microscopy is used here to capture the microstructures of commercial monolayer, tri-layer, and ceramic-coated lithium-ion battery polymer separators. Spatial variations in key structural parameters, including porosity, tortuosity factor and pore size distribution, are determined through the application of 3D quantification techniques and stereology. The architectures of individual layers in multi-layer membranes are characterised, revealing anisotropy in porosity, tortuosity factor and mean pore size of the three types of separator. Detailed structural properties of the individual layers of multi-layered membranes are then related with their expected effect on safety and rate capability of cells.

  1. Pigment analysis by Raman microscopy and portable X-ray fluorescence (pXRF) of thirteenth to fourteenth century illuminations and cuttings from Bologna

    Science.gov (United States)

    Chaplin, Tracey D.; Clark, Robin J. H.; Jones, Richard; Gibbs, Robert

    2016-12-01

    Non-destructive pigment analysis by Raman microscopy (RM) and portable X-ray fluorescence (pXRF) has been carried out on some Bolognese illuminations and cuttings chosen to represent the beginnings, evolution and height of Bolognese illuminated manuscript production. Dating to the thirteenth and fourteenth centuries and held in a private collection, the study provides evidence for the pigments generally used in this period. The results, which are compared with those obtained for other north Italian artwork, show the developments in usage of artistic materials and technique. Also addressed in this study is an examination of the respective roles of RM and pXRF analysis in this area of technical art history. This article is part of the themed issue "Raman spectroscopy in art and archaeology".

  2. Magnetization reversal of the domain structure in the anti-perovskite nitride Co{sub 3}FeN investigated by high-resolution X-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hajiri, T., E-mail: t.hajiri@numse.nagoya-u.ac.jp; Kuroki, Y.; Ando, H.; Sakakibara, H.; Ueda, K.; Asano, H. [Department of Crystalline Materials Science, Nagoya University, Nagoya 464-8603 (Japan); Finizio, S. [Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, Mainz D-55128 (Germany); Swiss Light Source, Paul Scherrer Institut, Villigen PSI CH-5232 (Switzerland); Vafaee, M.; Kläui, M. [Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, Mainz D-55128 (Germany); Kleibert, A.; Howald, L. [Swiss Light Source, Paul Scherrer Institut, Villigen PSI CH-5232 (Switzerland); Kronast, F. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, D-12489 Berlin (Germany)

    2016-05-14

    We performed X-ray magnetic circular dichroism (XMCD) photoemission electron microscopy imaging to reveal the magnetic domain structure of anti-perovskite nitride Co{sub 3}FeN exhibiting a negative spin polarization. In square and disc patterns, we systematically and quantitatively determined the statistics of the stable states as a function of geometry. By direct imaging during the application of a magnetic field, we revealed the magnetic reversal process in a spatially resolved manner. We compared the hysteresis on the continuous area and the square patterns from the magnetic field-dependent XMCD ratio, which can be explained as resulting from the effect of the shape anisotropy, present in nanostructured thin films.

  3. Monitoring of galvanic replacement reaction between silver nanowires and HAuCl4 by in situ transmission X-ray microscopy.

    Science.gov (United States)

    Sun, Yugang; Wang, Yuxin

    2011-10-12

    Galvanic replacement reaction between silver nanowires and an aqueous solution of HAuCl(4) has been successfully monitored in real time by using in situ transmission X-ray microscopy (TXM) in combination with a flow cell reactor. The in situ observations clearly show the morphological evolution of the solid silver nanowires to hollow gold nanotubes in the course of the reaction. Careful analysis of the images reveals that the galvanic replacement reaction on the silver nanowires involves multiple steps: (i) local initiation of pitting process; (ii) anisotropic etching of the silver nanowires and uniform deposition of the resulting gold atoms on the surfaces of the nanowires; and (iii) reconstruction of the nanotube walls via an Ostwald ripening process. The in situ TXM represents a promising approach for studying dynamic processes involved in the growth and chemical transformation of nanomaterials in solutions, in particular for nanostructures with dimensions larger than 50 nm.

  4. Structure, Mobility, and Composition of Transition Metal Catalyst Surfaces. High-Pressure Scanning Tunneling Microscopy and Ambient-Pressure X-ray Photoelectron Spectroscopy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Zhongwei [Univ. of California, Berkeley, CA (United States)

    2013-12-06

    Surface structure, mobility, and composition of transition metal catalysts were studied by high-pressure scanning tunneling microscopy (HP-STM) and ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) at high gas pressures. HP-STM makes it possible to determine the atomic or molecular rearrangement at catalyst surfaces, particularly at the low-coordinated active surface sites. AP-XPS monitors changes in elemental composition and chemical states of catalysts in response to variations in gas environments. Stepped Pt and Cu single crystals, the hexagonally reconstructed Pt(100) single crystal, and Pt-based bimetallic nanoparticles with controlled size, shape and composition, were employed as the model catalysts for experiments in this thesis.

  5. Discharge products of ionic liquid-based Li-O2 batteries observed by energy dependent soft x-ray transmission microscopy

    Science.gov (United States)

    Olivares-Marín, Mara; Sorrentino, Andrea; Pereiro, Eva; Tonti, Dino

    2017-08-01

    Products deposited on an O2-cathode discharged in ionic liquid electrolytes are analyzed by transmission soft X-ray microscopy (TXM) and compared to ether-based electrolytes, showing differences in morphology and chemical compositions. With both solvents we observe Li2O2 and LiO2 primary products in similar proportions. However, while as previously observed in tetraglyme an important reactivity takes place producing significant amount of carbonates, in ionic liquid-based electrolytes the formation of carbonates was almost negligible, confirming higher stability. Only when sample is intentionally air exposed before analysis, significant amounts of carbonates came up. However, LiOH crystallites are clearly recognized with the ionic liquid electrolyte. The abundance of these crystallites depends on both the LiTFSI concentration and the storage time of discharged electrodes, suggesting that they result from the reaction of water trace with primary discharge products.

  6. Comparative Characterization of InGaN/GaN Multiple Quantum Wells by Transmission Electron Microscopy, X-Ray Diffraction and Rutherford Backscattering

    Institute of Scientific and Technical Information of China (English)

    ZHOU Sheng-Qiang; WU Ming-Fang; YAO Shu-De; ZHANG Guo-Yi

    2005-01-01

    @@ The composition, elastic strain and structural defects of InGaN/GaN multiple quantum wells (MQWs) are comparatively investigated by using x-ray diffraction (XRD), transmission electron microscopy and Rutherford backscattering/channelling. The InGaN well layers are fully strained on GaN, i.e. the degree of relaxation is zero.The multilayered structure has a clear defined periodic thickness and abrupt interfaces. The In composition is deduced by XRD simulation. We show how the periodic structure, the In composition, the strain status and the crystalline quality of the InGaN/GaN MQWs can be determined and cross-checked by various techniques.

  7. Revealing the synergetic effects in Ni nanoparticle-carbon nanotube hybrids by scanning transmission X-ray microscopy and their application in the hydrolysis of ammonia borane

    Science.gov (United States)

    Zhao, Guanqi; Zhong, Jun; Wang, Jian; Sham, Tsun-Kong; Sun, Xuhui; Lee, Shuit-Tong

    2015-05-01

    The hybrids of carbon nanotubes (CNTs) and the supported Ni nanoparticles (NPs) have been studied by scanning transmission X-ray microscopy (STXM) and tested by the hydrolysis reaction of ammonia borane (AB, NH3BH3). Data clearly showed the existence of a strong interaction between Ni NPs and thin CNTs (C-O-Ni bonds), which favored the tunable (buffer) electronic structure of Ni NPs facilitating the catalytic process. The hydrolysis process of AB confirmed the hypothesis that the hybrids with a strong interfacial interaction would show superior catalytic performance, while the hybrids with a weak interfacial interaction show poor performance. Our results provide a wealth of detailed information regarding the electronic structure of the NP-CNT hybrids and provide guidance towards the rational design of high-performance catalysts for energy applications.The hybrids of carbon nanotubes (CNTs) and the supported Ni nanoparticles (NPs) have been studied by scanning transmission X-ray microscopy (STXM) and tested by the hydrolysis reaction of ammonia borane (AB, NH3BH3). Data clearly showed the existence of a strong interaction between Ni NPs and thin CNTs (C-O-Ni bonds), which favored the tunable (buffer) electronic structure of Ni NPs facilitating the catalytic process. The hydrolysis process of AB confirmed the hypothesis that the hybrids with a strong interfacial interaction would show superior catalytic performance, while the hybrids with a weak interfacial interaction show poor performance. Our results provide a wealth of detailed information regarding the electronic structure of the NP-CNT hybrids and provide guidance towards the rational design of high-performance catalysts for energy applications. Electronic supplementary information (ESI) available: Magnified TEM images, high resolution TEM images and the particle size distributions of the samples, the STXM results of a thick tube at different positions, XPS results, stability test. See DOI: 10.1039/c5nr01168j

  8. Morphology of gold nanoparticles determined by full-curve fitting of the light absorption spectrum. Comparison with X-ray scattering and electron microscopy data

    Science.gov (United States)

    Slyusarenko, Kostyantyn; Abécassis, Benjamin; Davidson, Patrick; Constantin, Doru

    2014-10-01

    UV-Vis absorption spectroscopy is frequently used to characterize the size and shape of gold nanoparticles. We present a full-spectrum model that yields reliable results for the commonly encountered case of mixtures of spheres and rods in varying proportions. We determine the volume fractions of the two populations, the aspect ratio distribution of the nanorods (average value and variance) and the interface damping parameter. We validate the model by checking the fit results against small-angle X-ray scattering and transmission electron microscopy data and show that correctly accounting for the polydispersity in aspect ratio is essential for a quantitative description of the longitudinal plasmon peak.UV-Vis absorption spectroscopy is frequently used to characterize the size and shape of gold nanoparticles. We present a full-spectrum model that yields reliable results for the commonly encountered case of mixtures of spheres and rods in varying proportions. We determine the volume fractions of the two populations, the aspect ratio distribution of the nanorods (average value and variance) and the interface damping parameter. We validate the model by checking the fit results against small-angle X-ray scattering and transmission electron microscopy data and show that correctly accounting for the polydispersity in aspect ratio is essential for a quantitative description of the longitudinal plasmon peak. Electronic supplementary information (ESI) available: TEM images of nanoparticles and detailed analysis, simplified relations for the AS model, alternative estimate for the concentration and discussion of the dielectric constant chosen for bulk gold. See DOI: 10.1039/c4nr04155k

  9. Raman microscopy and x-ray fluorescence analysis of pigments on medieval and Renaissance Italian manuscript cuttings

    OpenAIRE

    Burgio, Lucia; Clark, Robin J.H.; Hark, Richard R.

    2010-01-01

    Italian medieval and Renaissance manuscript cuttings and miniatures from the Victoria and Albert Museum were analyzed by Raman microscopy to compile a database of pigments used in different periods and different Italian regions. The palette identified in most manuscripts and cuttings was found to include lead white, gypsum, azurite, lazurite, indigo, malachite, vermilion, red lead, lead tin yellow (I), goethite, carbon, and iron gall ink. A few of the miniatures, such as the historiated capit...

  10. Extremity x-ray

    Science.gov (United States)

    ... degenerative) Bone tumor Broken bone (fracture) Dislocated bone Osteomyelitis (infection) Arthritis Other conditions for which the test ... Bone tumor Bone x-ray Broken bone Clubfoot Osteomyelitis X-ray Review Date 7/3/2016 Updated ...

  11. Abdominal x-ray

    Science.gov (United States)

    ... are, or may be, pregnant. Alternative Names Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also ...

  12. Scanning electron microscopy coupled with energy-dispersive X-ray spectrometry for quick detection of sulfur-oxidizing bacteria in environmental water samples

    Science.gov (United States)

    Sun, Chengjun; Jiang, Fenghua; Gao, Wei; Li, Xiaoyun; Yu, Yanzhen; Yin, Xiaofei; Wang, Yong; Ding, Haibing

    2017-01-01

    Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry (EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time (within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples.

  13. Scanning electron microscopy coupled with energy-dispersive X-ray spectrometry for quick detection of sulfur-oxidizing bacteria in environmental water samples

    Science.gov (United States)

    Sun, Chengjun; Jiang, Fenghua; Gao, Wei; Li, Xiaoyun; Yu, Yanzhen; Yin, Xiaofei; Wang, Yong; Ding, Haibing

    2016-03-01

    Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry (EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time (within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples.

  14. Polymer Compund Refractive Lenses for Hard X-ray Nanofocusing

    OpenAIRE

    Krywka, Christina; Last, Arndt; Marschall, Felix; Markus, Otto; Georgi, Sebastian; Mueller, Martin; Mohr, Jürgen

    2016-01-01

    Compound refractive lenses fabricated out of SU-8 negative photoresist have been used to generate a nanofocused, i.e. sub-μm sized X-ray focal spot at an X-ray nanodiffraction setup. X-ray microscopy and X-ray diffraction techniques have conceptually different demands on nanofocusing optical elements and so with the application of X-ray nanodiffraction in mind, this paper presents the results of an initial characterization of polymer lenses used as primary focusin...

  15. X-Ray Supernovae

    CERN Document Server

    Immler, S; Immler, Stefan; Lewin, Walter H.G.

    2002-01-01

    We present a review of X-ray observations of supernovae (SNe). By observing the (~0.1--100 keV) X-ray emission from young SNe, physical key parameters such as the circumstellar matter (CSM) density, mass-loss rate of the progenitor and temperature of the outgoing and reverse shock can be derived as a function of time. Despite intensive search over the last ~25 years, only 15 SNe have been detected in X-rays. We review the individual X-ray observations of these SNe and discuss their implications as to our understanding of the physical processes giving rise to the X-ray emission.

  16. Microscopic study of dental hard tissues in primary teeth with Dentinogenesis Imperfecta Type II: Correlation of 3D imaging using X-ray microtomography and polarising microscopy.

    Science.gov (United States)

    Davis, Graham R; Fearne, Janice M; Sabel, Nina; Norén, Jörgen G

    2015-07-01

    The aim of this study was to examine the histological appearance of dental hard tissues in primary teeth from children with DI using conventional polarised light microscopy and correlate that with 3D imaging using X-ray microtomograpy (XMT) to gain a further understanding of the dentine structure of teeth diagnosed with dentinogenesis imperfecta. Undecalcified sections of primary teeth from patients diagnosed with Dentinogenesis Imperfecta Type II were examined using polarised light microscopy. XMT was employed for 3D-imaging and analysis of the dentine. The polarised light microscopy and XMT revealed tubular structures in the dentine seen as vacuoles coinciding with the path of normal dentinal tubules but not continuous tubules. The size of the tubules was close to that of capillaries. The largest tubular structures had a direction corresponding to where the pulp tissue would have been located during primary dentine formation. The dysfunctional mineralisation of the dentine and obliteration of the pulp evidently leaves blood vessels in the dentine which have in the main been tied off and, in the undecalcified sections, appear as vacuoles. Although from radiographs, the pulp in teeth affected by Dentinogenesis Imperfect type II appears to be completely obliterated, a network of interconnected vessels may remain. The presence of large dentinal tubules and blood vessels, or the remnants of blood vessels, could provide a pathway for bacteria from the oral cavity. This might account for why some of these teeth develop periapical abscesses in spite of apparently having no pulp. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Determination of lead in clay enameled by X-ray fluorescence technique in Total reflection and by Scanning Electron Microscopy; Determinacion de plomo en esmaltado de barro por Fluorescencia de rayos X en reflexion total y Microscopia Electronica de Barrido

    Energy Technology Data Exchange (ETDEWEB)

    Zarazua O, G.; Carapia M, L. [Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Estado de Mexico (Mexico)

    2000-07-01

    This work has the objective of determining lead free in the glazed commercial stewing pans using the X-ray fluorescence technique in Total reflection (FRX) and the observation and semiquantitative determination of lead by Analytical Scanning Electron Microscopy (ASEM). (Author)

  18. Evolution of Cu-Zn-Si oxide catalysts in the course of reduction and reoxidation as studied by in situ X-ray diffraction analysis, transmission electron microscopy, and magnetic susceptibility methods

    NARCIS (Netherlands)

    Minyukova, T.P.; Shtertser, N.V.; Khassin, A.A.; Plyasova, L.M.; Kustova, G.N.; Zaikovskii, V.I.; Shvedenkov, Y.G.; Baronskaya, N.A.; van den Heuvel, J.C.; Kuznetsova, A.V.; Davydova, L.P.; Yur'eva, T.M.

    2008-01-01

    The reduced and reoxidized Cu-Zn-Si oxide catalysts as layered copper-zinc hydroxo silicates with the zincsilite structure were studied using in situ and ex situ X-ray diffraction analysis, transmission electron microscopy, and the temperature dependence of magnetic susceptibility. The catalysts wer

  19. Direct imaging by atomic force microscopy of surface-localized self-assembled monolayers on a cuprate superconductor and surface X-ray scattering analysis of analogous monolayers on the surface of water

    DEFF Research Database (Denmark)

    Schougaard, Steen B.; Reitzel, Niels; Bjørnholm, Thomas

    2007-01-01

    A self-assembled monolayer of CF3(CF2)(3)(CH2)(11)NH2 atop the (001) surface of the high-temperature superconductor YBa2Cu3O7-x was imaged by atomic force microscopy (AFM). The AFM images provide direct 2D-structural evidence for the epitaxial 5.5 angstrom square root 2 x root 2R45 degrees unit...... was studied by grazing-incidence X-ray diffraction and specular X-ray reflectivity. Structural differences and similarities between the water-supported and superconductor-localized monolayers are discussed....

  20. A study of the O/Ag(111) system with scanning tunneling microscopy and x-ray photoelectron spectroscopy at ambient pressures

    Science.gov (United States)

    Heine, Christian; Eren, Baran; Lechner, Barbara A. J.; Salmeron, Miquel

    2016-10-01

    The interaction of O2 with the Ag(111) surface was studied with scanning tunneling microscopy (STM) in the pressure range from 10- 9 Torr to 1 atm at room temperature and with X-ray photoelectron spectroscopy (XPS) up to 0.3 Torr O2 in the temperature range from RT to 413 K. STM images show that the Ag(111) surface topography is little affected in regions with large flat terraces, except for the appearance of mobile features due to oxygen atoms at pressures above 0.01 Torr. In regions where the step density is high, the surface became rough under 0.01 Torr of O2, due to the local oxidation of Ag. Various chemical states of oxygen due to chemisorbed, oxide and subsurface species were identified by XPS as a function of pressure and temperature. The findings from the STM images and XPS measurements indicate that formation of an oxide phase, the thermodynamically stable form at room temperature under ambient O2 pressure, is kinetically hindered in the flat terrace areas but proceeds readily in regions with high-step density.

  1. Computer-aided screening system for cervical precancerous cells based on field emission scanning electron microscopy and energy dispersive x-ray images and spectra

    Science.gov (United States)

    Jusman, Yessi; Ng, Siew-Cheok; Hasikin, Khairunnisa; Kurnia, Rahmadi; Osman, Noor Azuan Bin Abu; Teoh, Kean Hooi

    2016-10-01

    The capability of field emission scanning electron microscopy and energy dispersive x-ray spectroscopy (FE-SEM/EDX) to scan material structures at the microlevel and characterize the material with its elemental properties has inspired this research, which has developed an FE-SEM/EDX-based cervical cancer screening system. The developed computer-aided screening system consisted of two parts, which were the automatic features of extraction and classification. For the automatic features extraction algorithm, the image and spectra of cervical cells features extraction algorithm for extracting the discriminant features of FE-SEM/EDX data was introduced. The system automatically extracted two types of features based on FE-SEM/EDX images and FE-SEM/EDX spectra. Textural features were extracted from the FE-SEM/EDX image using a gray level co-occurrence matrix technique, while the FE-SEM/EDX spectra features were calculated based on peak heights and corrected area under the peaks using an algorithm. A discriminant analysis technique was employed to predict the cervical precancerous stage into three classes: normal, low-grade intraepithelial squamous lesion (LSIL), and high-grade intraepithelial squamous lesion (HSIL). The capability of the developed screening system was tested using 700 FE-SEM/EDX spectra (300 normal, 200 LSIL, and 200 HSIL cases). The accuracy, sensitivity, and specificity performances were 98.2%, 99.0%, and 98.0%, respectively.

  2. A Study of the Oxidation Behaviour of Pile Grade A (PGA Nuclear Graphite Using Thermogravimetric Analysis (TGA, Scanning Electron Microscopy (SEM and X-Ray Tomography (XRT.

    Directory of Open Access Journals (Sweden)

    Liam Payne

    Full Text Available Pile grade A (PGA graphite was used as a material for moderating and reflecting neutrons in the UK's first generation Magnox nuclear power reactors. As all but one of these reactors are now shut down there is a need to understand the residual state of the material prior to decommissioning of the cores, in particular the location and concentration of key radio-contaminants such as 14C. The oxidation behaviour of unirradiated PGA graphite was studied, in the temperature range 600-1050°C, in air and nitrogen using thermogravimetric analysis, scanning electron microscopy and X-ray tomography to investigate the possibility of using thermal degradation techniques to examine 14C distribution within irradiated material. The thermal decomposition of PGA graphite was observed to follow the three oxidation regimes historically identified by previous workers with limited, uniform oxidation at temperatures below 600°C and substantial, external oxidation at higher temperatures. This work demonstrates that the different oxidation regimes of PGA graphite could be developed into a methodology to characterise the distribution and concentration of 14C in irradiated graphite by thermal treatment.

  3. X-ray fluorescence (conventional and 3D) and scanning electron microscopy for the investigation of Portuguese polychrome glazed ceramics: Advances in the knowledge of the manufacturing techniques

    Energy Technology Data Exchange (ETDEWEB)

    Guilherme, A. [Departamento de Fisica da Faculdade de Ciencias, Centro de Fisica Atomica da Universidade de Lisboa, Av. Prof. Gama Pinto, 2, 1649-003 Lisboa (Portugal); Coroado, J. [Instituto Politecnico Tomar, Dep. Arte Conservacao and Restauro, P-2300313 Tomar (Portugal); Santos, J.M.F. dos [GIAN, Departamento de Fisica, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Luehl, L.; Wolff, T.; Kanngiesser, B. [Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin, Hardenbergstr. 36 D-10623 Berlin (Germany); Carvalho, M.L., E-mail: luisa@cii.fc.ul.pt [Departamento de Fisica da Faculdade de Ciencias, Centro de Fisica Atomica da Universidade de Lisboa, Av. Prof. Gama Pinto, 2, 1649-003 Lisboa (Portugal)

    2011-05-15

    This work shows the first analytical results obtained by X-Ray Fluorescence (XRF) (conventional and 3D) and Scanning Electron Microscopy with Energy Dispersive System (SEM-EDS) on original Portuguese ceramic pieces produced between the 16th and 18th centuries in Coimbra and Lisbon. Experts distinguished these productions based only on the color, texture and brightness, which originates mislabeling in some cases. Thanks to lateral and spatial resolution in the micrometer regime, the results obtained with {mu}-XRF were essential in determining the glaze and pigment thicknesses by monitoring the profile of the most abundant element in each 'layer'. Furthermore, the dissemination of these elements throughout the glaze is different depending on the glaze composition, firing temperature and on the pigment itself. Hence, the crucial point of this investigation was to analyze and understand the interfaces color/glaze and glaze/ceramic support. Together with the XRF results, images captured by SEM and the corresponding semi-quantitative EDS data revealed different manufacturing processes used by the two production centers. Different capture modes were suitable to distinguish different crystals from the minerals that confer the color of the pigments used and to enhance the fact that some of them are very well spread through the glassy matrix, sustaining the theory of an evolved and careful procedure in the manufacturing process of the glaze.

  4. An investigation into the subambient behavior of aqueous mannitol solutions using differential scanning calorimetry, cold stage microscopy, and X-ray diffractometry.

    Science.gov (United States)

    Kett, Vicky L; Fitzpatrick, Shaun; Cooper, Brett; Craig, Duncan Q M

    2003-09-01

    The subambient behavior of aqueous mannitol solutions is of considerable relevance to the preparation of freeze dried formulations. In this investigation the properties of 3% w/v mannitol solutions were investigated using differential scanning calorimetry (DSC), cold stage microscopy (CSM), and X-ray diffraction (XRD) to identify the thermal transitions and structural transformations undergone by this system. It was found that on cooling from ambient the system formed ice at circa -20 degrees C while a further exotherm was seen at approximately -30 degrees C. Upon reheating an endotherm was seen at circa -30 degrees C followed immediately by an exotherm at circa -25 degrees C. Temperature cycling indicated that the thermal transitions observed upon reheating were not reversible. Modulated temperature DSC (MTDSC) indicated that the transitions observed upon reheating corresponded to a glass transition immediately followed by recrystallization, XRD data showed that recrystallization was into the beta form. Annealing at -35 degrees C for 40 min prior to cooling and reheating resulted in a maximum enthalpy being observed for the reheating exotherm. It is concluded that on cooling 3% w/v aqueous mannitol solutions an amorphous phase is formed that subsequently recrystallises into the beta form. The study has also shown that DSC, CSM, and XRD are useful complementary techniques for the study of frozen systems.

  5. Characterization of the shape and line-edge roughness of polymer gratings with grazing incidence small-angle X-ray scattering and atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Hyo Seon; Chen, Xuanxuan; Rincon-Delgadillo, Paulina A.; Jiang, Zhang; Strzalka, Joseph; Wang, Jin; Chen, Wei; Gronheid, Roel; de Pablo, Juan J.; Ferrier, Nicola; Doxastakis, Manolis; Nealey, Paul F.

    2016-04-22

    Grazing-incidence small-angle X-ray scattering (GISAXS) is increasingly used for the metrology of substrate-supported nanoscale features and nanostructured films. In the case of line gratings, where long objects are arranged with a nanoscale periodicity perpendicular to the beam, a series of characteristic spots of high-intensity (grating truncation rods, GTRs) are recorded on a two-dimensional detector. The intensity of the GTRs is modulated by the three-dimensional shape and arrangement of the lines. Previous studies aimed to extract an average cross-sectional profile of the gratings, attributing intensity loss at GTRs to sample imperfections. Such imperfections are just as important as the average shape when employing soft polymer gratings which display significant line-edge roughness. Herein are reported a series of GISAXS measurements of polymer line gratings over a range of incident angles. Both an average shape and fluctuations contributing to the intensity in between the GTRs are extracted. The results are critically compared with atomic force microscopy (AFM) measurements, and it is found that the two methods are in good agreement if appropriate corrections for scattering from the substrate (GISAXS) and contributions from the probe shape (AFM) are accounted for.

  6. Electronic and geometric properties of Au nanoparticles on Highly Ordered Pyrolytic Graphite (HOPG) studied using X-ray Photoelectron Spectroscopy (XPS) and Scanning Tunneling Microscopy (STM).

    Science.gov (United States)

    Lopez-Salido, Ignacio; Lim, Dong Chan; Dietsche, Rainer; Bertram, Nils; Kim, Young Dok

    2006-01-26

    Au nanoparticles grown on mildly sputtered Highly Ordered Pyrolytic Graphite (HOPG) surfaces were studied using Scanning Tunneling Microscopy (STM) and X-ray Photoelectron Spectroscopy (XPS). The results were compared with those of Ag nanoparticles on the same substrate. By varying the defect densities of HOPG and the Au coverages, one can create Au nanoparticles in various sizes. At high Au coverages, the structures of the Au films significantly deviate from the ideal truncated octahedral form: the existence of many steps between different Au atomic layers can be observed, most likely due to a high activation barrier of the diffusion of Au atoms across the step edges. This implies that the particle growth at room temperature is strongly limited by kinetic factors. Hexagonal shapes of Au structures could be identified, indicating preferential growth of Au nanostructures along the (111) direction normal to the surface. In the case of Au, XPS studies reveal a weaker core level shift with decreasing particle size compared to the 3d level in similarly sized Ag particles. Also taking into account the Auger analysis of the Ag particles, the core level shifts of the metal nanoparticles on HOPG can be understood in terms of the metal/substrate charge transfer. Ag is (partially) positively charged, whereas Au negatively charged on HOPG. It is demonstrated that XPS can be a useful tool to study metal-support interactions, which plays an important role for heterogeneous catalysis, for example.

  7. Quick Detection of Sulfur Bacteria in Environmental Water Sample with SEM(scanning electron microscopy) coupled with Energy Dispersive X-ray Spectrometry

    Science.gov (United States)

    Sun, C.; Ding, H.; Wang, Y.; Jiang, F.; Li, X.; Gao, W.; Yin, X.

    2015-12-01

    Sulfur-oxidizing bacteria play important roles in global sulfur cycle. Sulfur bacteria detection has been largely dependent on targeted gene sequencing technology or traditional cell cultivation which usually takes from days to months to finish. This cannot meet the requirements of some time-sensitive samples and/or complicated environmental samples. Since Energy-Dispersive X-ray Spectrometry (EDS) can be used to simultaneously detect multiple elements including sulfur in a sample with minimal sample treatment, the technology was applied to detect sulfur bacteria through the high sulfur content in the bacteria cell. We report the application of SEM (scanning electron microscopy) imaging coupled with EDS mapping for direct and quick detection of sulfur oxidizer in contaminated environmental water samples. The presence of sulfur bacteria can be confirmed within 24 hours after sampling. Subsequent 16S RNA gene sequencing results found the bacteria detected had over 99% similarity to Chromatium Okenii, confirming the bacterium was a sulfur oxidizer. The developed technique made it possible to quickly detect sulfur oxidizer in environmental sample and could have wide applications in sulfur bacteria detection in environmental water samples.

  8. X-ray fluorescence microscopy demonstrates preferential accumulation of a vanadium-based magnetic resonance imaging contrast agent in murine colonic tumors.

    Science.gov (United States)

    Mustafi, Devkumar; Ward, Jesse; Dougherty, Urszula; Bissonnette, Marc; Hart, John; Vogt, Stefan; Karczmar, Gregory S

    2015-01-01

    Contrast agents that specifically enhance cancers on magnetic resonance imaging (MRI) will allow earlier detection. Vanadium-based chelates (VCs) selectively enhance rodent cancers on MRI, suggesting selective uptake of VCs by cancers. Here we report x-ray fluorescence microscopy (XFM) of VC uptake by murine colon cancer. Colonic tumors in mice treated with azoxymethane/dextran sulfate sodium were identified by MRI. Then a gadolinium-based contrast agent and a VC were injected intravenously; mice were sacrificed and colons sectioned. VC distribution was sampled at 120 minutes after injection to evaluate the long-term accumulation. Gadolinium distribution was sampled at 10 minutes after injection due to its rapid washout. XFM was performed on 72 regions of normal and cancerous colon from five normal mice and four cancer-bearing mice. XFM showed that all gadolinium was extracellular, with similar concentrations in colon cancers and normal colon. In contrast, the average VC concentration was twofold higher in cancers versus normal tissue (p < .002). Cancers also contained numerous "hot spots" with intracellular VC concentrations sixfold higher than the concentration in normal colon (p < .0001). No hot spots were detected in normal colon. This is the first direct demonstration that VCs selectively accumulate in cancer cells and thus may improve cancer detection.

  9. Application of Scanning Electron Microscopy/Energy-Dispersive X-Ray Spectroscopy for Characterization of Detrital Minerals in Karst Cave Speleothems.

    Science.gov (United States)

    Zupančič, Nina; Miler, Miloš; Šebela, Stanka; Jarc, Simona

    2016-02-01

    Micro-scale observations in karst caves help to identify different processes that shaped local morphology. Scanning electron microscopy/energy-dispersive X-ray spectroscopy inspection of speleothems from two karst caves in Slovenia, Predjama and Črna Jama, confirmed the presence of sub-angular to sub-rounded detrital fragments of clay minerals, feldspars, quartz, Fe-oxides/hydroxides, rutile and Nb-rutile, xenotime, kassite, allanite, fluorapatite, epidote, ilmenite, monazite, sphene, and zircon, between 2 and 50 μm across. These occur in porous layers separating calcite laminae in the clayey coating on the layer below the surface of the speleothems, and are also incorporated within actual crystals. It is likely that they are derived from the weathered rocks of the Eocene flysch. Probably they were first transported into the caves by floodwaters forming cave sediments. Later, depending upon the climate conditions, they were moved by air currents or by water to the surface of active speleothems. They might also be redeposited from overlying soils enriched with wind-transported minerals from the flysch, or from higher passages filled with weathered flysch sediment, by drip water percolating through the fissured limestone. As some of the identified minerals are carriers of rare earth elements, Ti and Zr, their presence could affect any palaeoclimatic interpretations that are based upon the geochemical composition of the speleothems.

  10. Comparative Study of Metal Quantification in Neurological Tissue Using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry Imaging and X-ray Fluorescence Microscopy.

    Science.gov (United States)

    Davies, Katherine M; Hare, Dominic J; Bohic, Sylvain; James, Simon A; Billings, Jessica L; Finkelstein, David I; Doble, Philip A; Double, Kay L

    2015-07-07

    Redox-active metals in the brain mediate numerous biochemical processes and are also implicated in a number of neurodegenerative diseases. A number of different approaches are available for quantitatively measuring the spatial distribution of biometals at an image resolution approaching the subcellular level. Measured biometal levels obtained using laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS; spatial resolution 15 μm × 15 μm) were within the range of those obtained using X-ray fluorescence microscopy (XFM; spatial resolution 2 μm × 7 μm) and regional changes in metal concentration across discrete brain regions were replicated to the same degree. Both techniques are well suited to profiling changes in regional biometal distribution between healthy and diseased brain tissues, but absolute quantitation of metal levels varied significantly between methods, depending on the metal of interest. Where all possible variables affect metal levels, independent of a treatment/phenotype are controlled, either method is suitable for examining differences between experimental groups, though, as with any method for imaging post mortem brain tissue, care should be taken when interpreting the total metal levels with regard to physiological concentrations.

  11. A Study of the Oxidation Behaviour of Pile Grade A (PGA) Nuclear Graphite Using Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and X-Ray Tomography (XRT).

    Science.gov (United States)

    Payne, Liam; Heard, Peter J; Scott, Thomas B

    2015-01-01

    Pile grade A (PGA) graphite was used as a material for moderating and reflecting neutrons in the UK's first generation Magnox nuclear power reactors. As all but one of these reactors are now shut down there is a need to understand the residual state of the material prior to decommissioning of the cores, in particular the location and concentration of key radio-contaminants such as 14C. The oxidation behaviour of unirradiated PGA graphite was studied, in the temperature range 600-1050°C, in air and nitrogen using thermogravimetric analysis, scanning electron microscopy and X-ray tomography to investigate the possibility of using thermal degradation techniques to examine 14C distribution within irradiated material. The thermal decomposition of PGA graphite was observed to follow the three oxidation regimes historically identified by previous workers with limited, uniform oxidation at temperatures below 600°C and substantial, external oxidation at higher temperatures. This work demonstrates that the different oxidation regimes of PGA graphite could be developed into a methodology to characterise the distribution and concentration of 14C in irradiated graphite by thermal treatment.

  12. Corrosive effects of fluoride on titanium: investigation by X-ray photoelectron spectroscopy, atomic force microscopy, and human epithelial cell culturing.

    Science.gov (United States)

    Stájer, Anette; Ungvári, Krisztina; Pelsoczi, István K; Polyánka, Hilda; Oszkó, Albert; Mihalik, Erzsébet; Rakonczay, Zoltán; Radnai, Márta; Kemény, Lajos; Fazekas, András; Turzó, Kinga

    2008-11-01

    High fluoride (F(-)) concentrations and acidic pH impair the corrosion resistance of titanium (Ti). Effects of F(-)-containing caries-preventive prophylactic rinses, and gels on Ti were investigated by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Human epithelial cell attachment and proliferation were investigated by dimethylthiazol-diphenyl tetrazolium bromide (MTT) and protein content assays. Aqueous 1% NaF solution (3800 ppm F(-), pH 4.5) or high (12,500 ppm) F(-) content gel (pH 4.8) strongly corroded the surface and modified its composition. XPS revealed formation of a strongly bound F(-)-containing complex (Na(2)TiF(6)). AFM indicated an increase in roughness (R(a)) of the surfaces: 10-fold for the NaF solution and smaller for the gel or a mouthwash (250 ppm F(-), pH 4.4). MTT revealed that cell attachment was significantly increased by the gel, but was not disturbed by either the mouthwash or the NaF. Cell proliferation determined by MTT decreased significantly only for the NaF-treated samples; protein content assay experiments showed no such effect. This study indicates that epithelial cell culturing results can depend on the method used, and the adverse effects of a high F(-) concentration and low pH should be considered when prophylactic gels are applied by patients with Ti implants or other dental devices.

  13. Chemical Differentiation of Osseous and Nonosseous Materials Using Scanning Electron Microscopy-Energy-Dispersive X-Ray Spectrometry and Multivariate Statistical Analysis.

    Science.gov (United States)

    Meizel-Lambert, Cayli J; Schultz, John J; Sigman, Michael E

    2015-11-01

    Identification of osseous materials is generally established on gross anatomical features. However, highly fragmented or taphonomically altered materials may be problematic and may require chemical analysis. This research was designed to assess the use of scanning electron microscopy-energy-dispersive X-ray spectrometry (SEM/EDX), elemental analysis, and multivariate statistical analysis (principal component analysis) for discrimination of osseous and nonosseous materials of similar chemical composition. Sixty samples consisting of osseous (human and nonhuman bone and dental) and non-osseous samples were assessed. After outliers were removed a high overall correct classification of 97.97% was achieved, with 99.86% correct classification for osseous materials. In addition, a blind study was conducted using 20 samples to assess the applicability for using this method to classify unknown materials. All of the blind study samples were correctly classified resulting in 100% correct classification, further demonstrating the efficiency of SEM/EDX and statistical analysis for differentiation of osseous and nonosseous materials. © 2015 American Academy of Forensic Sciences.

  14. Surface characterization of 7S and 11S globulin powders from soy protein examined by X-ray photoelectron spectroscopy and scanning electron microscopy.

    Science.gov (United States)

    Zhao, Xiaoyan; Chen, Jun; Zhu, Qingjun; Du, Fangling; Ao, Qiang; Liu, Jie

    2011-09-01

    In this study the surface composition of 7S and 11S globulin powders from soybean proteins by aqueous buffer and reverse micelle extractions had been examined using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Analysis by XPS revealed that the O and N atomic percentage of 7S and 11S globulin surfaces from bis(2-ethylhexyl) sodium sulfosuccinate (AOT) reverse micelle was higher than from aqueous buffer, but the C atomic percentage was lower. The O/C ratio of the 7S globulin powder from aqueous buffer and reverse micelle was similar while significant differences were obtained in the O/C ratio of the 11S globulin powder, N/C atom ratios of the 7S and 11S globulin powders and high-resolution XPS C 1s, N 1s, O 1s spectra. Powder microstructure after reverse micelle treatment showed the presence of small pores, indicating the effect of reverse micelle on the 7S and 11S globulin structure. The obtained results indicated that the reverse micelle could affect the C, O and N components on the surface of soybean proteins. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Optical and structural properties in type-II InAlAs/AlGaAs quantum dots observed by photoluminescence, X-ray diffraction and transmission electron microscopy

    Science.gov (United States)

    Ben Daly, A.; Craciun, D.; Laura Ursu, E.; Lemaître, A.; Maaref, M. A.; Iacomi, F.; Vasile, B. S.; Craciun, V.

    2017-10-01

    We present the effects of AlGaAs alloy composition on InAlAs quantum dots (QDs) optical and structural properties. Photoluminescence (PL) analysis of samples having a variety of aluminium composition values covering type-II transitions clearly in QDs showed the presence of two transitions X-Sh and X-Ph. High-resolution X-ray diffraction (HRXRD) investigations showed that the layers grew epitaxially on the GaAs substrate, with no relaxation regardless the Al content of AlGaAs layer. From the reciprocal space map (RSM) investigation around (004) and (115) diffraction peaks, it was shown that the InAlAs layer is fully strained, the in-plane lattice parameters (a and b, a = b) being identical to those of GaAs substrate, while the c lattice parameter was dependent on the In and Al concentrations, being larger than that of the substrate. High-resolution transmission electronic microscopy (HRTEM) investigations confirmed that films grew epitaxially on the GaAs substrate with no visible dislocations or other major defects within the InAlAs/GaAlAs QDs structure.

  16. Scanning transmission X-ray microscopy probe for in situ mechanism study of graphene-oxide-based resistive random access memory.

    Science.gov (United States)

    Nho, Hyun Woo; Kim, Jong Yun; Wang, Jian; Shin, Hyun-Joon; Choi, Sung-Yool; Yoon, Tae Hyun

    2014-01-01

    Here, an in situ probe for scanning transmission X-ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K- and O K-edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron-based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K-edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies.

  17. In Situ Observation of Water Dissociation with Lattice Incorporation at FeO Particle Edges Using Scanning Tunneling Microscopy and X-ray Photoelectron Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Xingyi [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Lee, Junseok [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Wang, Congjun [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Matranga, Christopher [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Aksoy, Funda [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nigde University, Nigde (Turkey). Dept. of Physics; Liu, Zhi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-03-15

    The dissociation of H2O and formation of adsorbed hydroxyl groups, on FeO particles grown on Au(111) were identified with in situ,: X:ray photoelectron spectroscopy (XPS) at water pressures ranging from 3 x 10-8 to 0.1 Torr. The facile dissociation of H2O takes place at FeO particle edges, and it was successfully observed in situ With atomically resolved scanning tunneling microscopy (STM). The in situ STM studies show that adsorbed hydroxyl groups were formed exclusively along the edges of the FeO particles with the 0 atom becoming directly incorporated into the oxide crystalline lattice The STM results are consistent with coordinatively unsaturated ferrous (CUF) sites along the FeO particle edge causing the observed reactivity with H2O. Our results also directly illustrate how structural defects and under.-coordinated sites participate in chemical reactions.

  18. Photocorrosion of coupled CdS/CdSe photoelectrodes coated with ZnO. Atomic force microscopy and X-ray diffraction studies

    Energy Technology Data Exchange (ETDEWEB)

    Rincon, M.E.; Sanchez, M. [UNAM, Temixco (Mexico). Centro de Investigacion en Energia; Ruiz-Garcia, J. [UASLP, San Luis Potosi (Mexico). Inst. de Fisica

    1998-10-01

    The stability of photoelectrochemical cells based on chemically deposited CdS/CdSe coupled films has been examined. Changes in surface structure and composition of coated and uncoated CdS{sub 250}/CdSe coupled films as well as CdSe films have been examined by atomic force microscopy and X-ray diffraction. The superior stability at short times of the coupled system, compared to CdSe, is related to the increase in the hexagonal character (stronger bonding) and the smaller recombination rate of the photogenerated carriers. At large operation times, the lower stability of the coupled system is related to band opening, which increases the oxidation rates of the passivating Se/S layer. The recrystallization illuminated CdSe photoanodes, and coupled films working in the dark can be explained by the presence of surface states and back reactions. Stable short-circuit currents were obtained with coupled films coated with a thin layer (350 {angstrom}) of ZnO. It is likely that oxidation and redeposition of the protective ZnO film competes for hole consumption. The rough morphology of the coated photoelectrodes correlated to a substantial increase in surface area that resembles ZnO particulate film electrodes sensitized by CdSe and CdS.

  19. A case of hut lung: scanning electron microscopy with energy dispersive x-ray spectroscopy analysis of a domestically acquired form of pneumoconiosis.

    Science.gov (United States)

    Mukhopadhyay, Sanjay; Gujral, Manmeet; Abraham, Jerrold L; Scalzetti, Ernest M; Iannuzzi, Michael C

    2013-07-01

    Hut lung is a pneumoconiosis caused by exposure to smoke derived from biomass fuels used for cooking in poorly ventilated huts. We report, to our knowledge, the first analysis of the dust deposited in the lungs in hut lung by scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM/EDS). A Bhutanese woman presented with shortness of breath and an abnormal chest radiograph. Chest CT scan showed innumerable tiny bilateral upper lobe centrilobular nodules. Transbronchial biopsy revealed mild interstitial fibrosis with heavy interstitial deposition of black dust. SEM/EDS showed that the dust was carbonaceous, with smaller yet substantial numbers of silica and silicate particles. Additional history revealed use of a wood/coal-fueled stove in a small, poorly ventilated hut for 45 years. The possibility of hut lung should be considered in women from countries where use of biomass-fueled stoves for cooking is common. Our findings support the classification of this condition as a mixed-dust pneumoconiosis.

  20. X-Ray Polarimetry

    CERN Document Server

    Kaaret, Philip

    2014-01-01

    We review the basic principles of X-ray polarimetry and current detector technologies based on the photoelectric effect, Bragg reflection, and Compton scattering. Recent technological advances in high-spatial-resolution gas-filled X-ray detectors have enabled efficient polarimeters exploiting the photoelectric effect that hold great scientific promise for X-ray polarimetry in the 2-10 keV band. Advances in the fabrication of multilayer optics have made feasible the construction of broad-band soft X-ray polarimeters based on Bragg reflection. Developments in scintillator and solid-state hard X-ray detectors facilitate construction of both modular, large area Compton scattering polarimeters and compact devices suitable for use with focusing X-ray telescopes.

  1. Twin domain imaging in topological insulator Bi2Te3 and Bi2Se3 epitaxial thin films by scanning X-ray nanobeam microscopy and electron backscatter diffraction

    Science.gov (United States)

    Harcuba, Petr; Veselý, Jozef; Lesnik, Andreas; Bauer, Guenther; Springholz, Gunther; Holý, Václav

    2017-01-01

    The twin distribution in topological insulators Bi2Te3 and Bi2Se3 was imaged by electron backscatter diffraction (EBSD) and scanning X-ray diffraction microscopy (SXRM). The crystal orientation at the surface, determined by EBSD, is correlated with the surface topography, which shows triangular pyramidal features with edges oriented in two different orientations rotated in the surface plane by 60°. The bulk crystal orientation is mapped out using SXRM by measuring the diffracted X-ray intensity of an asymmetric Bragg peak using a nano-focused X-ray beam scanned over the sample. By comparing bulk- and surface-sensitive measurements of the same area, buried twin domains not visible on the surface are identified. The lateral twin domain size is found to increase with the film thickness.

  2. Development of a laser-based heating system for in situ synchrotron-based X-ray tomographic microscopy.

    Science.gov (United States)

    Fife, Julie L; Rappaz, Michel; Pistone, Mattia; Celcer, Tine; Mikuljan, Gordan; Stampanoni, Marco

    2012-05-01

    Understanding the formation of materials at elevated temperatures is critical for determining their final properties. Synchrotron-based X-ray tomographic microscopy is an ideal technique for studying such processes because high spatial and temporal resolutions are easily achieved and the technique is non-destructive, meaning additional analyses can take place after data collection. To exploit the state-of-the-art capabilities at the tomographic microscopy and coherent radiology experiments (TOMCAT) beamline of the Swiss Light Source, a general-use moderate-to-high-temperature furnace has been developed. Powered by two diode lasers, it provides controlled localized heating, from 673 to 1973 K, to examine many materials systems and their dynamics in real time. The system can also be operated in various thermal modalities. For example, near-isothermal conditions at a given sample location can be achieved with a prescribed time-dependent temperature. This mode is typically used to study isothermal phase transformations; for example, the formation of equiaxed grains in metallic systems or to nucleate and grow bubble foams in silicate melts under conditions that simulate volcanic processes. In another mode, the power of the laser can be fixed and the specimen moved at a constant speed in a user-defined thermal gradient. This is similar to Bridgman solidification, where the thermal gradient and cooling rate control the microstructure formation. This paper details the experimental set-up and provides multiple proofs-of-concept that illustrate the versatility of using this laser-based heating system to explore, in situ, many elevated-temperature phenomena in a variety of materials.

  3. X-ray and Cryo-electron Microscopy Structures of Monalysin Pore-forming Toxin Reveal Multimerization of the Pro-form.

    Science.gov (United States)

    Leone, Philippe; Bebeacua, Cecilia; Opota, Onya; Kellenberger, Christine; Klaholz, Bruno; Orlov, Igor; Cambillau, Christian; Lemaitre, Bruno; Roussel, Alain

    2015-05-22

    β-Barrel pore-forming toxins (β-PFT), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. Monalysin has been recently identified as a β-PFT that contributes to the virulence of Pseudomonas entomophila against Drosophila. It is secreted as a pro-protein that becomes active upon cleavage. Here we report the crystal and cryo-electron microscopy structure of the pro-form of Monalysin as well as the crystal structures of the cleaved form and of an inactive mutant lacking the membrane-spanning region. The overall structure of Monalysin displays an elongated shape, which resembles those of β-pore-forming toxins, such as Aerolysin, but is devoid of a receptor-binding domain. X-ray crystallography, cryo-electron microscopy, and light-scattering studies show that pro-Monalysin forms a stable doughnut-like 18-mer complex composed of two disk-shaped nonamers held together by N-terminal swapping of the pro-peptides. This observation is in contrast with the monomeric pro-form of the other β-PFTs that are receptor-dependent for membrane interaction. The membrane-spanning region of pro-Monalysin is fully buried in the center of the doughnut, suggesting that upon cleavage of pro-peptides, the two disk-shaped nonamers can, and have to, dissociate to leave the transmembrane segments free to deploy and lead to pore formation. In contrast with other toxins, the delivery of 18 subunits at once, nearby the cell surface, may be used to bypass the requirement of receptor-dependent concentration to reach the threshold for oligomerization into the pore-forming complex.

  4. Synthesis and surface characterization of a patterned cuprite sample: Preparatory step in the evaluation scheme of an X-ray-excited optical microscopy system

    Energy Technology Data Exchange (ETDEWEB)

    Sabbe, Pieter-Jan [Department of Analytical Chemistry, Ghent University, Krijgslaan 281-S12, Ghent (Belgium); Dowsett, Mark G. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); De Keersmaecker, Michel [Department of Analytical Chemistry, Ghent University, Krijgslaan 281-S12, Ghent (Belgium); Hand, Matthew [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Thompson, Paul [XMaS – The UK CRG, ESRF – The European Synchrotron, CS 40220, 38043 Grenoble Cedex 9 (France); Department of Physics, University of Liverpool, Liverpool L69 7ZX (United Kingdom); Adriaens, Annemie, E-mail: annemie.adriaens@ugent.be [Department of Analytical Chemistry, Ghent University, Krijgslaan 281-S12, Ghent (Belgium)

    2015-03-30

    Highlights: • Periodically arranged cuprite reference material samples are presented. • The produced reference material is used for characterization of new XEOL microscope. • A priori sample surface characterization was done by XPS, XAS, XEOL–XANES and XRD. • Results indicated a heterogeneous mixture of mainly Cu{sub 2}O with CuO at near surface. • The produced patina provides intense optical luminescence upon X-ray bombardment. - Abstract: The synthesis and characterization of a reference sample containing a distinct geometrical pattern of Cu{sub 2}O (cuprite) are described. The sample is to be used as an assessment sample to evaluate a newly developed X-ray-excited optical luminescence (XEOL) microscope, built for non-destructive chemical imaging of metal and other surfaces. The sample was produced by heating in a reducing flame and subsequent air exposure. It was characterized both qualitatively and quantitatively using X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy in both fluorescence mode (XAS) and optical luminescence mode (XEOL–XAS) and X-ray diffraction (XRD). Results indicate the presence of a layered structure comprising a heterogeneous mixture of cuprite and tenorite (CuO) with mainly cuprite (91.4%) in the near-surface regions and larger amounts of tenorite in the top 1–3 nm. The cuprite produced via this protocol was found to provide intense optical luminescence upon X-ray bombardment, which is particularly useful during the evaluation of the microscope.

  5. X-Ray

    Science.gov (United States)

    ... You may be allowed to remain with your child during the test. If you remain in the room during the X-ray exposure, you'll likely be asked to wear a lead apron to shield you from unnecessary exposure. After the X-ray ...

  6. Dental x-rays

    Science.gov (United States)

    ... X-rays are a form of high energy electromagnetic radiation. The x-rays penetrate the body to form ... for detecting cavities, unless the decay is very advanced and deep. Many ... The amount of radiation given off during the procedure is less than ...

  7. X-Ray Surveys

    CERN Document Server

    Giommi, P; Perri, M

    1998-01-01

    A review of recent developments in the field of X-ray surveys, especially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparison between the measurements in the hard band and extrapolations from ROSAT counts, that takes into proper account the observed distribution of spectral slopes, is presented. Direct comparisons between deep ROSAT and BeppoSAX images show that most hard X-ray sources are also detected at soft X-ray energies. This may indicate that heavily cutoff sources, that should not be detectable in the ROSAT band but are expected in large numbers from unified AGN schemes, are in fact detected because of the emerging of either non-nuclear components, or of reflected, or partially transmitted nuclear X-rays. These soft components may complicate the estimation of the soft X-ray luminosity function and cosmological evolution of AGN.

  8. X-ray Polarimetry

    Science.gov (United States)

    Kallman, T.

    In spite of the recent advances in X-ray instrumentation, polarimetry remains an area which has been virtually unexplored in the last 20 years. The scientific motivation to study polarization has increased during this time: emission models designed to repro- duce X-ray spectra can be tested using polarization, and polarization detected in other wavelength bands makes clear predictions as to the X-ray polarization. Polarization remains the only way to infer geometrical properties of sources which are too small to be spatially resolved. At the same time, there has been recent progress in instrumen- tation which is likely to allow searches for X-ray polarization at levels significantly below what was possible for early detectors. In this talk I will review the history of X-ray polarimetry, discuss some experimental techniques and the scientific problems which can be addressed by future experiments.

  9. X-rays and magnetism.

    Science.gov (United States)

    Fischer, Peter; Ohldag, Hendrik

    2015-09-01

    Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized x-rays have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of x-rays and their degree of coherence at next generation x-ray facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on x-ray dichroism effects. Selected examples of current research will demonstrate the potential and future directions of these techniques.

  10. Duodenal crypt health following exposure to Cr(VI): Micronucleus scoring, γ-H2AX immunostaining, and synchrotron X-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Chad M.; Wolf, Jeffrey C.; Elbekai, Reem H.; Paranjpe, Madhav G.; Seiter, Jennifer M.; Chappell, Mark A.; Tappero, Ryan V.; Suh, Mina; Proctor, Deborah M.; Bichteler, Anne; Haws, Laurie C.; Harris, Mark A.

    2015-08-01

    Lifetime exposure to high concentrations of hexavalent chromium [Cr(VI)] in drinking water results in intestinal damage and an increase in duodenal tumors in B6C3F1 mice. To assess whether these tumors could be the result of a direct mutagenic or genotoxic mode of action, we conducted a GLP-compliant 7-day drinking water study to assess crypt health along the entire length of the duodenum. Mice were exposed to water (vehicle control), 1.4, 21, or 180 ppm Cr(VI) via drinking water for 7 consecutive days. Crypt enterocytes in Swiss roll sections were scored as normal, mitotic, apoptotic, karyorrhectic, or as having micronuclei. A single oral gavage of 50 mg/kg cyclophosphamide served as a positive control for micronucleus induction. Exposure to 21 and 180 ppm Cr(VI) significantly increased the number of crypt enterocytes. Micronuclei and γ-H2AX immunostaining were not elevated in the crypts of Cr(VI)-treated mice. In contrast, treatment with cyclophosphamide significantly increased numbers of crypt micronuclei and qualitatively increased γ-H2AX immunostaining. Synchrotron-based X-ray fluorescence (XRF) microscopy revealed the presence of strong Cr fluorescence in duodenal villi, but negligible Cr fluorescence in the crypt compartment. Together, these data indicate that Cr(VI) does not adversely effect the crypt compartment where intestinal stem cells reside, and provide additional evidence that the mode of action for Cr(VI)-induced intestinal cancer in B6C3F1 mice involves chronic villous wounding resulting in compensatory crypt enterocyte hyperplasia.

  11. Characterization of wet precipitation by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in the metropolitan area of Porto Alegre, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Montanari Migliavacca, Daniela [Instituto de Biociencias, Programa de Pos-Graduacao em Ecologia, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil); Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler, RS. Rua Carlos Chagas 55/802, 90030-020 Porto Alegre, RS (Brazil); Calesso Teixeira, Elba, E-mail: gerpro.pesquisa@fepam.rs.gov.br [Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler, RS. Rua Carlos Chagas 55/802, 90030-020 Porto Alegre, RS (Brazil); Gervasoni, Fernanda; Vieira Conceicao, Rommulo [Instituto de Geociencias, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil); Raya Rodriguez, Maria Teresa [Instituto de Biociencias, Programa de Pos-Graduacao em Ecologia, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil)

    2009-11-15

    The purpose of this study is to assess the composition of wet precipitation in three sites of the metropolitan area of Porto Alegre. Besides the variables usually considered, such as pH, conductivity, major ions (Cl{sup -}, NO{sub 3}{sup -}, F{sup -}, SO{sub 4}{sup 2-}, Na{sup +}, K{sup +}, Mg{sup 2+}, NH{sub 4}{sup +} and Ca{sup 2+}) and metallic elements (Cd, Co, Cr, Cu, Fe, Mn and Ni), the suspended matter was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), with energy dispersive system (EDS), for better identification of possible anthropogenic material in this wet precipitation. Results showed an alkaline pH in the samples analyzed and higher concentrations for Na{sup +}, Cl{sup -} and SO{sub 4}{sup 2-}. The acidification and neutralization potential between anions (SO{sub 4}{sup 2-} + NO{sub 3}{sup -}) and cations (Ca{sup 2+} + Mg{sup 2+} + K{sup +} + NH{sub 4}{sup +}) showed a good correlation (0.922). The metallic elements with highest values were Zn, Fe and Mn. Results of XRD identified the presence of some minerals such as quartz, feldspar, mica, clay, carbonates and sulfates. In samples analyzed with SEM, we detected pyroxene, biotite, amphibole and oxides. Cluster analysis (CA) was applied to the data matrix to identify potential pollution sources of metals (natural or anthropogenic) and the association with minerals found in the analysis of SEM.

  12. Primary cumulus platinum minerals in the Monts de Cristal Complex, Gabon: magmatic microenvironments inferred from high-definition X-ray fluorescence microscopy

    Science.gov (United States)

    Barnes, Stephen J.; Fisher, Louise A.; Godel, Bélinda; Pearce, Mark A.; Maier, Wolfgang D.; Paterson, David; Howard, Daryl L.; Ryan, Christopher G.; Laird, Jamie S.

    2016-03-01

    An unusual occurrence of Pt-enriched pyroxenites in the Monts de Cristal igneous complex is characterized by unusually high ratios of Pt to other platinum-group elements (PGEs) and very low Cu and sulfide contents. Synchrotron X-ray fluorescence microscopy was used to identify over a hundred discrete grains of platinum minerals and relate their occurrence to textural associations in the host heteradcumulate orthopyroxenites. Element associations, backed up by FIB-SEM and PIXE probe observations, indicate that most of the Pt is associated with either As- or trace Cu-Ni-rich sulfides, or both. Some of the Pt-As grains can be identified as sperrylite, and most are likely to be Pt-Fe alloy. The relative abundances and volumes of Pt minerals to sulfide minerals are very large compared with typical magmatic sulfides. Almost all of the grains observed lie at or within a few tens of μm of cumulus orthopyroxene grain boundaries, and there is no significant difference between the populations of grains located inside or outside plagioclase oikocrysts. These oikocrysts are inferred to have crystallized either at the cumulus stage or very shortly thereafter, on the basis of their relationship to Ti enrichment in the margins of pyroxene grains not enclosed in oikocrysts. This relationship precludes a significant role of trapped intercumulus liquid in Pt deposition or mobilization and also allows a confident inference that Pt-rich and Pt-As-enriched phases precipitated directly from the magma at the cumulus stage. These observations lead to the conclusion that fractionation of Pt from other PGEs in this magmatic system is a consequence of a solubility limit for solid Pt metal and/or Pt arsenide.

  13. Gadolinium released from MR contrast agents is deposited in brain tumors: in situ demonstration using scanning electron microscopy with energy dispersive X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Daniel; Davis, Richard L.; Crawford, Judith A.; Abraham, Jerrold L. (Dept. of Pathology, SUNY Upstate Medical Univ., Syracuse, NY (United States)), e-mail: abrahamj@upstate.edu

    2010-12-15

    Background: Gadolinium (Gd)-containing MRI contrast agents (GdCA) are widely used in studies of brain tumors, and a number of reports suggest that under certain conditions, such as renal failure, Gd may be released from GdCA into patient's tissues. Whether this may happen in abnormal tissues in the absence of renal failure has not been studied. Purpose: To test the hypothesis that the local retention of GdCA resulting from brain tumor-associated alterations in the blood-brain barrier (BBB) may result in the deposition of Gd released from the GdCA, depending on stability. Material and Methods: In this retrospective study, 30 selected brain tumor biopsies from 28 patients (taken before and after an institutional switch from a less stable to an intermediate stable GdCA) were searched for Gd-containing deposits using scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Relevant histories and laboratory results were obtained through institutional electronic records. Associations between the presence of deposits and other variables were tested for statistical significance using the two-tailed Fisher's exact test. Results: Insoluble deposits containing Gd associated with phosphorus and calcium were found in seven biopsies from five patients. These deposits were found in patients with estimated GFRs above 53 ml/min, and were detected more often in those receiving GdCA before the switch from a less stable to an intermediate stable GdCA (P = 0.04), and may be more frequent in patients receiving more than one contrast-enhanced MR scan (P = 0.15). Conclusion: Gd-containing deposits are present in brain tumors following contrast-enhanced MR scans in patients without severe renal disease. Further studies are needed to assess the clinical importance of the deposits we observed and to determine whether they are also found in other conditions that alter the integrity of the BBB

  14. Interaction of human plasma fibrinogen with commercially pure titanium as studied with atomic force microscopy and X-ray photoelectron spectroscopy.

    Science.gov (United States)

    Keere, Isabel Van De; Willaert, Ronnie; Hubin, Annick; Vereecken, Jean

    2008-03-04

    The surface of a biomaterial interacts with the body fluid upon implantation in the human body. The biocompatibility of a material is strongly influenced by the adsorption of proteins onto the surface. Titanium is frequently used as a biomaterial for implants in orthopedics and cardiovascular devices. Understanding the biocompatibility is very important to improve implants. The surface chemistry of an implant material and its influence on the interaction with body fluid is crucial in that perspective. The main goal of this study was to investigate the conformation of human plasma fibrinogen (HPF) adsorbed on commercially pure titanium (CP Ti) on a molecular level by means of ex situ atomic force microscopy (AFM). With X-ray photoelectron spectroscopy combined with argon ion beam depth profiling, it was shown that the oxide layer present at the surface was mainly composed of TiO2, with a small percentage of Ti2O3. Ex situ AFM imaging showed the conformation of HPF on CP Ti. Single molecules and aggregates of fibrinogen were observed. The trinodular structure of single HPF molecules (two spherical D domains at the distal ends of the extended molecule and the central spherical E domain) adsorbed onto CP Ti was visualized. Aggregate formation through the connection of the D domains of the HPF molecules was observed on CP Ti. The alphaC domains of HPF were not visible on CP Ti. The ex situ AFM images indicated conformational changes of HPF upon adsorption onto CP Ti. The conformation of the adsorbed HPF molecules was different on mica and titanium. The difference in wettability between both substrates caused a larger spread of the protein on the CP Ti surface and thus resulted in a larger perturbation to the native structure of HPF as compared to mica.

  15. Effect of polymers on the nanostructure and on the carbonation of calcium silicate hydrates: a scanning transmission X-ray microscopy study

    KAUST Repository

    Ha, J.

    2011-09-07

    This study investigated the effects of organic polymers (polyethylene glycol and hexadecyltrimethylammonium) on structures of calcium silicate hydrates (C-S-H) which is the major product of Portland cement hydration. Increased surface areas and expansion of layers were observed for all organic polymer modified C-S-H. The results from attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopic measurements also suggest lowered water contents in the layered structures for the C-S-H samples that are modified by organic polymers. Scanning transmission X-ray microscopy (STXM) results further supports this observation. We also observed difference in the extent of C-S-H carbonation due to the presence of organic polymers. No calcite formed in the presence of HDTMA whereas formation of calcite was observed with C-S-H sample modified with PEG. We suggest that the difference in the carbonation reaction is possibly due to the ease of penetration and diffusion of the CO 2. This observation suggests that CO 2 reaction strongly depends on the presence of organic polymers and the types of organic polymers incorporated within the C-S-H structure. This is the first comprehensive study using STXM to quantitatively characterize the level of heterogeneity in cementitious materials at high spatial and spectral resolutions. The results from BET, XRD, ATR-FTIR, and STXM measurements are consistent and suggest that C-S-H layer structures are significantly modified due to the presence of organic polymers, and that the chemical composition and structural differences among the organic polymers determine the extent of the changes in the C-S-H nanostructures as well as the extent of carbonation reaction. © 2011 Springer Science+Business Media, LLC.

  16. X-ray crystallography

    Science.gov (United States)

    2001-01-01

    X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

  17. X-ray lasers

    CERN Document Server

    Elton, Raymond C

    2012-01-01

    The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...