Zeitschriftenartikel: „Mapping of elemental distribution“

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Pereira, G. R., H. S. Rocha, M. J. Anjos, P. C. M. A. Farias, C. A. Pérez und R. T. Lopes. „Elemental distribution mapping on breast tissue samples“. European Journal of Radiology 68, Nr. 3 (Dezember 2008): S104—S108. http://dx.doi.org/10.1016/j.ejrad.2008.04.047.

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Houk, Carol S., und Catherine J. Page. „Mapping the elemental distribution in sol-gel derived ceramics“. Advanced Materials 8, Nr. 2 (Februar 1996): 173–76. http://dx.doi.org/10.1002/adma.19960080218.

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3

Leapman, R. D., und C. R. Swyt. „Quantitative Electron Energy Loss Mapping“. Proceedings, annual meeting, Electron Microscopy Society of America 43 (August 1985): 404–5. http://dx.doi.org/10.1017/s0424820100118898.

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The intensity of a characteristic electron energy loss spectroscopy (EELS) image does not, in general, directly reflect the elemental concentration. In fact, the raw core loss image can give a misleading impression of the elemental distribution. This is because the measured core edge signal depends on the amount of plural scattering which can vary significantly from region to region in a sample. Here, we show how the method for quantifying spectra due to Egerton et al. can be extended to maps.

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NAAB, F. U., F. D. MCDANIEL, J. L. DUGGAN, B. C. BOLING und D. SMITH. „ELEMENTAL MAPPING OF A POST OAK LEAF USING A PROTON MICROPROBE“. International Journal of PIXE 17, Nr. 03n04 (Januar 2007): 177–82. http://dx.doi.org/10.1142/s012908350700123x.

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Elemental distributions in a post oak leaf was measured using the Particle-Induced X-ray Emission (PIXE) technique and a proton microbeam at energy of 3 MeV with spatial resolution of 10 μm. The elements detected in this sample were Mg , Al , Si , P , S , Cl , K , Ca , Cr , Mn , Fe , Cu , Zn , Br , Rb , and Sr . Among them, spatial differences in the distribution of nine elements were observed between the vascular and mesophyll tissue. Si , Cl , K , and Ca were mostly accumulated in vascular tissue, while Mg , P , S , Cr , and Mn were for the most part accumulated in the mesophyll. The distribution of Ca appeared to follow cell wall contours. The distribution of some of these elements is compared to the function of the elements in living tissue and future possibilities for this type of investigation are discussed.

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Liang, Long C. „Quantitative mineral compositional analysis using digital x-ray images“. Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 746–47. http://dx.doi.org/10.1017/s042482010008804x.

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Digital x-ray imaging (DXI) has been utilized to display spatial elemental distribution and to conduct quantitative elemental compositional mapping on various samples. The quantitative elemental compositional mapping technique, however, requires the use of an advanced image analysis and computer system to display elemental concentration maps. In this study, a simplified DXI technique is used to achieve two goals: (1) display elemental distribution, and (2) conduct quantitative mineral compositional analysis using stored digital x-ray maps. The analytical procedure of this technique can be easily implemented to similar instruments in any laboratory.Quantitative analysis with the simplified DXI technique is performed using background-corrected elemental pixel intensities instead of using net x-ray counts as in a conventional electron microprobe analysis. In this study, digital x-ray mapping has been conducted using a JEOL 733 electron microprobe automated with a Tracor Northern (TN) 5500/5600 system. A TN image analysis program, IPP, was used to acquire all digital x-ray maps at an accelerating voltage of 15 kV and a beam current of 15 nA.

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Marini, Carlo, Josep Roqué-Rosell, Marc Campeny, Shiva Toutounchiavval und Laura Simonelli. „MAP2XANES: a Jupyter interactive notebook for elemental mapping and XANES speciation“. Journal of Synchrotron Radiation 28, Nr. 4 (19.05.2021): 1245–52. http://dx.doi.org/10.1107/s1600577521003593.

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MAP2XANES is an intuitive Jupyter notebook that automatizes the analysis of synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy for the characterization of complex and heterogeneous samples. The notebook uses basic modules and functions from Numpy, Scipy, Pandas, iPywidgets and Matplotlib libraries for a powerful data reduction process that, in just a few clicks, guides the user through the visualization of elemental maps, space-resolved absorption spectra and their automatized analysis. In particular, by means of linear combination fit of the XANES spectra, the notebook determines the chemical species distribution in the sample under investigation. The direct output of the analysis process is the correlation between the different elemental distributions and the spatial localization of the chemical species detected. An application to mineralogy is thus presented, analyzing the Mn2+, Mn3+ and Mn4+ distribution in a mineral sample of hausmannite (Mn2+Mn2 3+O4), courtesy of the Museum of Natural Science of Barcelona.

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Ikematsu, Y., D. Shindo, T. Oikawa und M. Kersker. „Elemental Mapping of Materials Using Omega Filter and Imaging Plate“. Microscopy and Microanalysis 6, S2 (August 2000): 216–17. http://dx.doi.org/10.1017/s1431927600033572.

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Elemental microanalysis has been important in materials characterization, since the elemental distribution strongly affects the property of various materials. A recently developed post-column energy filter coupled with a slow scan CCD camera makes it possible to carry out elemental mapping with a transmission electron microscope. Here, we develop the elemental mapping technique utilizing the omega filter and imaging plates (3760x3000 pixels). Since the data obtained from the imaging plates consist of a large number of pixels, fine and detailed elemental analysis will be expected.Energy-filtered images were obtained by a JEM-2010 electron microscope installed with an omega-type energy filter, and they were recorded on imaging plates (FDL-UR-V:25 μm/pixel). The width of an energy-selecting slit was set to be 20 eV. Elemental maps were obtained from the energy-filtered images using the three window technique. Special care was taken to reduce the image shifts among the three filtered images used in the three-window method.

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Leapman, Richard D., Eva Kocsis, Guo Zhang, Thomas L. Talbot und Patrice Laquerriere. „Mapping Cellular Elemental Distributions in Three Dimensions“. Microscopy and Microanalysis 10, S02 (August 2004): 1182–83. http://dx.doi.org/10.1017/s1431927604881881.

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Kawasaki, M., F. Hosokawa, G. Fritz und N. Kale. „Drift-Corrected High Magnification Elemental X-Ray Mappng“. Microscopy and Microanalysis 6, S2 (August 2000): 418–19. http://dx.doi.org/10.1017/s1431927600034589.

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Chemical analysis in a TEM has usually been done as a manual point analysis by forming a probe of an appropriate size for the area of interest. This type of local analysis may provide enough information from the selected area, but these days when materials properties are found to be deeply dependent on chemical distribution, one needs to do a higher dimensional analysis using a systematic line scan or mapping.Since the advent of the Field Emission Gun (FEG), chemical mapping using X-rays (EDS mapping) or inelastic scattered electrons (Energy Filtering mapping) has become more and more commonly used due to the extremely high resolution information available in the chemical map. Compared to the energy filtered mapping, EDS maps take longer to acquire due to the use of the scanned probe over the area but EDS mapping allows a wider choice of elements to map due to the wider energy range it covers.

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DeMiglio, D. S. „Ore characterization by digital color x-ray mapping“. Proceedings, annual meeting, Electron Microscopy Society of America 44 (August 1986): 850–51. http://dx.doi.org/10.1017/s0424820100145595.

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A silver ore was examined by scanning electron microscopy (SEM) to aid in the selection of an extraction process by documenting the distribution and association of elements found within a representative sampling of ore particles. Through the use of color image processing similar to that used by Krakow digital X-ray maps were acquired which showed elemental distributions indicative of mineral phases previously identified by X-ray powder diffraction. Prior to this investigation silver particles (<10 microns) were observed to be randomly distributed throughout the host rock which was primarily a silica gangue.

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Harvey, Maggie-Anne, Peter D. Erskine, Hugh H. Harris, Gillian K. Brown, Elizabeth A. H. Pilon-Smits, Lachlan W. Casey, Guillaume Echevarria und Antony van der Ent. „Distribution and chemical form of selenium in Neptunia amplexicaulis from Central Queensland, Australia“. Metallomics 12, Nr. 4 (2020): 514–27. http://dx.doi.org/10.1039/c9mt00244h.

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Elemental mapping of selenium in the hyperaccumulator Neptunia amplexicaulis determined whole plant and tissue level selenium distribution. The total concentrations and chemical forms of selenium are also reported for this species.

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Nakajima, Hideaki, Takahiro Morimoto, Ying Zhou, Kazufumi Kobashi, Seisuke Ata, Takeo Yamada und Toshiya Okazaki. „Nonuniform functional group distribution of carbon nanotubes studied by energy dispersive X-ray spectrometry imaging in SEM“. Nanoscale 11, Nr. 44 (2019): 21487–92. http://dx.doi.org/10.1039/c9nr07619k.

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TOQUE, JAY ARRE, und ARI IDE-EKTESSABI. „RECONSTRUCTION OF ELEMENTAL DISTRIBUTION IMAGES FROM SYNCHROTRON RADIATION X-RAY FLUORESCENCE SPECTRA“. International Journal of Modern Physics B 23, Nr. 04 (10.02.2009): 557–69. http://dx.doi.org/10.1142/s0217979209049978.

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Synchrotron radiation X-ray fluorescence spectroscopy (SRXRF) is a powerful technique for studying trace elements in biological samples and other materials in general. Its features including capability to perform measurements in air and water, noncontact and nondestructive assay are superior to other elemental analysis techniques. In this study, a technique for reconstructing elemental distribution mapping of trace elements from spectral data was developed. The reconstruction was made possible by using the measured fluorescent signals to obtain local differences in elemental concentrations. The proposed technique features interpolation and background subtraction using matrix transformations of the spectral data to produce an enhanced distribution images. It is achieved by employing polychromatic or monochromatic color assignments proportional to the fluorescence intensities for displaying single-element or multiple-element distributions respectively. Some typical applications (i.e., macrophage and tissue surrounding an implant) were presented and the samples were imaged using the proposed method. The distribution images of the trace elements of the selected samples were used in conjunction with other analytical techniques to draw relevant observations, which cannot be achieved using conventional techniques such as metallic uptake and corresponding cellular response. The elemental distribution images produced from this study were found to have better quality compared to images produced using other analytical techniques (e.g., SIMS, PIXE, XPS, etc).

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McFadden, A., B. Wade, C. Izzo, B. M. Gillanders, C. E. Lenehan und A. Pring. „Quantitative electron microprobe mapping of otoliths suggests elemental incorporation is affected by organic matrices: implications for the interpretation of otolith chemistry“. Marine and Freshwater Research 67, Nr. 7 (2016): 889. http://dx.doi.org/10.1071/mf15074.

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In an effort to understand the mechanism of otolith elemental incorporation, the distribution of strontium (Sr) and sulfur (S) in otoliths of Platycephalus bassensis was investigated in conjunction with otolith growth patterns. Optimisation of electron probe microanalysis (EPMA) quantitative mapping achieved both high spatial resolution (<3µm) and two-dimensional visualisation of the fine scale Sr and S distributions in otoliths of P. bassensis with minimal damage. Electron backscatter diffraction (EBSD) mapping confirmed that grain growth is aligned with the otolith c-axis, with grain orientation independent of both otolith elemental composition and growth patterns. Results showed a linear correlation between Sr and S distribution (R2=0.86), and a clear association with the otolith growth patterns determined by scanning electron microscopy. Further examination by laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) showed that incorporation of Mg and Ba appeared independent of both S distribution and the growth patterns. The results suggest that element incorporation into the otolith is linked to the organic composition in the endolymph during mineralisation, and the organic matrices may assist, in part, the uptake of Sr. Thus, these findings may have significant implications for the interpretation of otolith Sr chemistry.

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Singh, Vivek K., Durgesh Kumar Tripathi, Xianglei Mao, Richard E. Russo und Vassilia Zorba. „Elemental Mapping of Lithium Diffusion in Doped Plant Leaves Using Laser-Induced Breakdown Spectroscopy (LIBS)“. Applied Spectroscopy 73, Nr. 4 (21.03.2019): 387–94. http://dx.doi.org/10.1177/0003702819830394.

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Mapping of element distributions and diffusion processes in plant tissue has great significance for understanding the systematic uptake, transport, and accumulation of nutrients and harmful elements in plants, and for studying the interaction between plants and the environment. In this work, we used laser-induced breakdown spectroscopy (LIBS) to study the elemental accumulation of Li and its diffusion in plant leaves. The spatially resolved information that LIBS offers, combined with its high sensitivity to light elements make this technology highly advantageous for the analysis of Li. Laser-induced breakdown spectroscopy mapping of Li-doped leaf samples is used to directly visualize the diffusion of Li in the plant leaf and study its distribution as a function of LiCl solution exposure time. Our findings demonstrate that diffusion of Li in plant leaves occurs though their veins (i.e., bundles of vascular tissue) and that Li concentration decreases as we move away from the LiCl exposure site. These results underline the importance of veins in transportation of toxic elements in plants, and mapping of their distribution can be instrumental in the development of possible remediation approaches for managing Li toxicity.

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WATANABE, Y., S. HOMMA-TAKEDA, M. YUKAWA, Y. NISHIMURA und H. IMASEKI. „APPLICATION OF MICRO-PIXE AND ICP-MS TO ANALYSIS OF ELEMENTAL DISTRIBUTION IN ROOT APEX OF PLANTS“. International Journal of PIXE 11, Nr. 03n04 (Januar 2001): 125–31. http://dx.doi.org/10.1142/s0129083501000189.

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Micro-PIXE and inductively coupled plasma mass spectrometry (ICP-MS) were applied to elemental distribution analyses in plant root apex which is composed of various types of tissues and cells in different developmental stages. ICP-MS was so sensitive that a large number of elements including Na, Mg, P, S, K, Ca, Mn, Fe, Cu, Zn, Se, Rb, Sr and Cs could be determined quantitatively. These fourteen elements included almost all the essential elements for plant growth. Only a rough estimation, however, could be obtained by ICP-MS for the elemental distribution at the tissue level, by analyzing sections from the root apex. On the other hand, micro-PIXE was effective for detailed mappings of elemental distributions. The images of elemental distributions were obtained for Na, Mg, P, S, K, Ca, Mn, Fe and Zn, corresponding to the microscopic images of the root structures. The localizations of P, K and Zn in some tissues were observed by the mappings. These results indicated that micro-PIXE and ICP-MS have different, but complementary abilities for the investigation of elemental distributions in plant tissues.

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Brock, Judith M., und Max T. Otten. „X-ray mapping without STEM“. Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 508–9. http://dx.doi.org/10.1017/s042482010017027x.

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A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

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De Samber, B., S. Vanblaere, R. Evens, K. De Schamphelaere, G. Wellenreuther, F. Ridoutt, G. Silversmit et al. „Dual detection X-ray fluorescence cryotomography and mapping on the model organism Daphnia magna“. Powder Diffraction 25, Nr. 2 (Juni 2010): 169–74. http://dx.doi.org/10.1154/1.3397114.

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Micro-X-ray fluorescence (μ-XRF) is a rapidly evolving analytical technique which allows visualising the trace level metal distributions within a specimen in an essentially nondestructive manner. At second generation synchrotron radiation sources, detection limits at the sub-parts per million level can be obtained with micrometer resolution, while at third generation sources the spatial resolution can be better than 100 nm. Consequently, the analysis of metals within biological systems using micro- and nano-X-ray fluorescence imaging is a quickly developing field of research. Since X-ray fluorescence is a scanning technique, the elemental distribution within the sample should not change during analysis. Biological samples pose challenges in this context due to their high water content. A dehydration procedure is commonly used for sample preparation enabling an analysis of the sample under ambient temperature conditions. Unfortunately, a potential change in elemental redistribution during the sample preparation is difficult to verify experimentally and therefore cannot be excluded completely. Creating a cryogenic sample environment allowing an analysis of the sample under cryogenic condition is an attractive alternative but not available on a routine basis. In this article, we make a comparison between the elemental distributions obtained by micro-SR-XRF within a chemically fixed and a cryogenically frozen Daphnia magna, a model organism to study the environmental impact of metals. In what follows, we explore the potential of a dual detector setup for investigating a full ecotoxicological experiment. Next to conventional 2D analysis, dual detector X-ray fluorescence cryotomography is illustrated and the potential of its coupling with laboratory absorption micro-CT for investigating the tissue-specific elemental distributions within this model organism is highlighted.

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Mulware, Stephen Juma. „The Review of Nuclear Microscopy Techniques: An Approach for Nondestructive Trace Elemental Analysis and Mapping of Biological Materials“. Journal of Biophysics 2015 (18.11.2015): 1–7. http://dx.doi.org/10.1155/2015/740751.

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The properties of many biological materials often depend on the spatial distribution and concentration of the trace elements present in a matrix. Scientists have over the years tried various techniques including classical physical and chemical analyzing techniques each with relative level of accuracy. However, with the development of spatially sensitive submicron beams, the nuclear microprobe techniques using focused proton beams for the elemental analysis of biological materials have yielded significant success. In this paper, the basic principles of the commonly used microprobe techniques of STIM, RBS, and PIXE for trace elemental analysis are discussed. The details for sample preparation, the detection, and data collection and analysis are discussed. Finally, an application of the techniques to analysis of corn roots for elemental distribution and concentration is presented.

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Bovin, J. O. „EFTEM Elemental Mapping of Particles Frozen in Amorphous Solutions“. Microscopy and Microanalysis 6, S2 (August 2000): 2–3. http://dx.doi.org/10.1017/s1431927600032505.

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The preparation of frozen amorphous nano-meter thin films of solutions containing particles, and imaging with energy filtered TEM, opens for the first time the possibility to map the elemental distribution in solids interacting with liquids. The future possible areas of research in solution include: dynamic of crystal growth processes, adsorption mechanisms, ion exchange, structure determination of nano-sized solids in equilibrium with different solvents, etc.The sample preparation uses a controlled-environment vitrification system. Solidification of the liquid phase was achieved by plunging the solution, suspended in the holes of a lacy carbon on a copper grid, into liquid ethane (-174 °C). The specimen was transferred into the microscope by an Oxford CT3500 cryo-holder. The specimen temperature in the microscope column can be kept at -183 °C. The thickness of the vitrified film's, including the particles, should be about 50-100 nm or preferably less. The Philips CM120 BioTWIN Cryo microscope, here used for cryo-EFTEM, has a focal length of 6 nun and a structural resolution of 0.4 nm.

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Yukawa, M., H. Imaseki und O. Yukawa. „MICRO-BEAM SCANNING PIXE IN NIRS AND THE APPLICATION TESTS TO BIOLOGICAL SAMPLES“. International Journal of PIXE 10, Nr. 01n02 (Januar 2000): 71–75. http://dx.doi.org/10.1142/s0129083500000109.

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Micro-beam scanning system for PIXE analysis newly installed in National Institute of Radiological Sciences (NIRS) was introduced in this paper. Fine ring structure of a fish scale was observed using elemental mapping with proton micro-beam scanning. Pollen was analyzed as one example of single cell to demonstrate the elemental distribution. The minimum size of the proton beam is estimated as 0.4×0.65 μ m .

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Amemiya, Susumu, Toshio Masuda, Liviu Popa-Simil und Liviu Mateescu. „Mapping of aerosols' elemental distribution in two zones in Romania by PIXE analysis“. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 118, Nr. 1-4 (September 1996): 403–7. http://dx.doi.org/10.1016/0168-583x(95)01088-2.

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Leapman, R. D., und J. A. Hunt. „Compositional mapping by electron energy loss spectroscopy“. Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 8–9. http://dx.doi.org/10.1017/s042482010008434x.

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Compositional maps of a thin specimen can be obtained using electron energy loss spectroscopy (EELS) to measure the two-dimensional distribution of inelastic scattering processes. These maps may be acquired both in the energy-filtering transmission electron microscope (EFTEM) and in the scanning transmission electron microscope (STEM). An advantage of EFTEM is that data from large numbers of pixels are collected simultaneously making the technique favorable for detection of high local elemental concentrations. However in the EFTEM images at different energy losses must be acquired sequentially, complicating the analysis of weak spectral features which require careful subtraction of the background intensity. Early attempts to utilize the STEM for EELS mapping were limited by the performance of serial detectors. The availability of parallel detectors and inexpensive PC-type computers with sufficient storage and speed has generated new interest in using the STEM for EELS elemental mapping. In particular the concept of EELS spectrum-imaging has been introduced by Jeanguillaume and Colliex.

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Crozier, P. A. „Energy-filtered chemical mapping: Current applications to materials science“. Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 958–59. http://dx.doi.org/10.1017/s0424820100172528.

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Elemental mapping is a powerful technique for elucidating the distribution of elements on the nanometer scale in materials with complex morphologies. In electron microscopy, mapping is usually performed on a scanning transmission electron microscope (STEM) fitted with a field emission gun (FEG) using the techniques of energy-dispersive x-ray spectroscopy (EDX) or electron energy-loss spectroscopy (EELS). However, recent advances in spectrometer design and digital image recording have stimulated renewed interest in energy-filtered imaging and elemental mapping with a conventional transmission electron microscope. Here, some applications of energy-filtered chemical mapping in materials science are described.Experiments were conducted on a Zeiss 912 operating at 120 kV with a thermal source and equipped with an omega filter spectrometer. A variable width slit in the spectrometer image plane allows energy-filtered images to be formed on the microscope viewing screen. These images are digitally recorded using a Gatan 679 slow-scan CCD camera with 1024 pixels.

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Mazlee, Mohd Noor, und Shamsul Baharin Jamaludin. „The Effects of Superheating Treatment on Distribution of Eutectic Silicon Particles in A357-Continuous Stainless Steel Composite“. Advanced Materials Research 620 (Dezember 2012): 511–16. http://dx.doi.org/10.4028/www.scientific.net/amr.620.511.

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In the present study, superheating treatment has been applied on A357 reinforced with 0.5 wt.% (Composite 1) and 1.0 wt.% (Composite 2) continuous stainless steel composite. In Composite 1, the microstructure displayed poor bonding between matrix and reinforcement interface. Poor bonding associated with large voids also can be seen in Composite 1. The results also showed that coarser eutectic silicon (Si) particles were less intensified around the matrix-reinforcement interface. From energy dispersive spectrometry (EDS) elemental mapping, it was clearly shown that the distribution of eutectic Si particles were less concentrated at poor bonding regions associated with large voids. Meanwhile in Composite 2, the microstructure displayed good bonding combined with more concentrated finer eutectic Si particles around the matrix-reinforcement interface. From EDS elemental mapping, it was clearly showed more concentrated of eutectic Si particles were distributed at the good bonding area. The superheating treatment prior to casting has influenced the microstructure and tends to produce finer, rounded and preferred oriented α-Al dendritic structures.

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Bhatt, M., C. Wöhler, A. Grumpe, N. Hasebe und M. Naito. „Global mapping of lunar refractory elements: multivariate regression vs. machine learning“. Astronomy & Astrophysics 627 (Juli 2019): A155. http://dx.doi.org/10.1051/0004-6361/201935773.

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Context.The quantitative estimation of elemental concentrations at the spatial resolution of hyperspectral near-infrared (NIR) images of the lunar surface is an important tool for understanding the processes relevant for the origin and evolution of the Moon.Aims.We aim to map the abundances of the elements Fe, Ca, and Mg at a typical accuracy of about 1 wt.% at the spatial resolution of the Moon Mineralogy Mapper (M3) instrument on-board Chandrayaan-1 lunar mission.Methods.The NIR reflectance of the lunar regolith is an integrated response to the presence of refractory elements and soil alteration processes. Our approach was to define a combination of spectral parameters that are robust with respect to the effects of soil maturity. We calibrated the spectral parameters with respect to elemental abundances measured by the Lunar Prospector Gamma Ray Spectrometer (LP GRS) and the Kaguya GRS (KGRS). For this purpose, we compared a classical multivariate linear regression (MLR) approach and the machine learning based support vector regression (SVR) technique applied to M3global observations.Results.The M3-based global elemental maps are consistent in distribution and range with the LP GRS and KGRS elemental maps and do not show artifacts in immature areas such as small fresh craters. The results derived using MLR and SVR are compared to sample-based ground truth data of the Apollo and Luna sample-return sites, where the root-mean-square deviations obtained by the two regression models are similar.Conclusions.The main advantage of the proposed new algorithm is its ability to minimize artifacts due to space-weathering effects. The elemental maps of Mg and Ca provide additional information and reveal structures not always visible in the Fe map. The global elemental abundance maps derived for the fully calibrated M3observations might thus serve as important tools to investigate the lunar geology and evolution.

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Ma, Limei, Zijian Xu, Zhi Guo, Benjamin Watts, Jinyou Lin, Xiangzhi Zhang und Renzhong Tai. „Three-dimensional fast elemental mapping by soft X-ray dual-energy focal stacks imaging“. Journal of Synchrotron Radiation 28, Nr. 3 (30.03.2021): 924–29. http://dx.doi.org/10.1107/s1600577521002903.

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The three-dimensional (3D) dual-energy focal stacks (FS) imaging method has been developed to quickly obtain the spatial distribution of an element of interest in a sample; it is a combination of the 3D FS imaging method and two-dimensional (2D) dual-energy contrast imaging based on scanning transmission soft X-ray microscopy (STXM). A simulation was firstly performed to verify the feasibility of the 3D elemental reconstruction method. Then, a sample of composite nanofibers, polystyrene doped with ferric acetylacetonate [Fe(acac)3], was further investigated to quickly reveal the spatial distribution of Fe(acac)3 in the sample. Furthermore, the data acquisition time was less than that for STXM nanotomography under similar resolution conditions and did not require any complicated sample preparation. The novel approach of 3D dual-energy FS imaging, which allows fast 3D elemental mapping, is expected to provide invaluable information for biomedicine and materials science.

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Vogel-Mikuš, Katarina, Paula Pongrac und Primož Pelicon. „Micro-PIXE elemental mapping for ionome studies of crop plants“. International Journal of PIXE 24, Nr. 03n04 (Januar 2014): 217–33. http://dx.doi.org/10.1142/s0129083514400142.

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In order to maintain homeostasis and consequent optimal cell functioning and integrity and/or to avoid toxicity, proper allocation of elements at organ, tissue, cellular and subcellular level is needed. Studies of element localization are therefore crucial to reveal the mechanisms of element trafficking and also tolerance and toxicity. Moreover, studies of localization and speciation of trace elements in grains of staple crops are also of high applicative value, allowing one to determine major and trace element concentrations in different grain tissues without possible contamination. In the last decade, a remarkable progress has been made in the development and application of different 2D imaging techniques in complex biological systems, especially in the sense of improved lateral resolution and sensitivity. The superiority of micro-PIXE over other 2D imaging techniques lies in its wide elemental range (from sodium (Na) to uranium (U)), high elemental sensitivity below micron spatial resolution and fully quantitative element concentration analysis. The aim of this review is to summarize the latest development of micro-PIXE for imaging of the distribution of major and trace elements in crop plants with emphasis on sample preparation methodologies and post-imaging analysis. Case studies of element localization in the grains of major crop plants are also presented.

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Kothleitner, G., und H. A. Brink. „Spectroscopy and Imaging With Energy-Filtering Tems: Parameters That Matter“. Microscopy and Microanalysis 6, S2 (August 2000): 158–59. http://dx.doi.org/10.1017/s1431927600033286.

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Spectroscopy and imaging techniques based on electron energy-losses (EELS), which are accessible through energy-filtering transmission electron microscopes (EFTEMs), have proven to be important tools in both materials and life science investigations.The two most widely used techniques on commercially available EFTEMs are elastic imaging and elemental mapping. Elastic imaging enhances image resolution and contrast by extracting the zero-loss signal and eliminating the inelastic background, whereas elemental mapping, which involves signals coming from element-specific inner-shell ionization edges, is employed to form two dimensional elemental distribution images. In both cases relatively large energy windows of a range of 10 to 30eVare typically used to form energy-filtered images with usually low to moderately high magnifications.There is however much more information available in an EELS spectrum, which is contained in the detailed fine structure within 0-20eV of a core excitation edge (ELNES) or in the very low energy-loss up to 5eV.

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Afyon, Semih, Frank Krumeich und Jennifer L. M. Rupp. „A shortcut to garnet-type fast Li-ion conductors for all-solid state batteries“. Journal of Materials Chemistry A 3, Nr. 36 (2015): 18636–48. http://dx.doi.org/10.1039/c5ta03239c.

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Scanning transmission electron microscopy (STEM) images and elemental mapping of cubic c-Li_6.4Ga_0.2La₃Zr₂O₁₂ powders (synthesized at 650 °C) indicating the homogeneous distribution of Zr (red), La (green) and Ga (blue) over the nanostructures.

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Kindness, Andrew, Chandra N. Sekaran und Jörg Feldmann. „Two-Dimensional Mapping of Copper and Zinc in Liver Sections by Laser Ablation–Inductively Coupled Plasma Mass Spectrometry“. Clinical Chemistry 49, Nr. 11 (01.11.2003): 1916–23. http://dx.doi.org/10.1373/clinchem.2003.022046.

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Abstract Background: Metals are not homogeneously distributed in organ tissues. Although most mapping techniques, such as histologic staining methods, have been developed for element imaging on a subcellular level, many suffer from either low precision or poor detection limits. Therefore, small variations in elemental distribution cannot be identified. We developed a method for two-dimensional mapping of trace elements to identify the influence of metabolic zonation by the liver on trace element distribution. Methods: A prepared homogeneous Certified Reference Material (CRM; LGC 7112, pig liver) was used to characterize the laser ablation–inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-MS) in terms of precision. Different isotopes for copper and zinc were monitored, and the use of carbon as an internal standard was investigated to correct for differences in ablation efficiency to identify the most precise mapping technique for liver samples. Results: For the homogeneous CRM, the reproducibility of the copper and zinc signals was ∼3–24% depending on spot size and number of pulses. When carbon was used as an internal standard, the reproducibility was improved significantly. Line scan signals over a length of 1.5 mm were more precise [relative SD (RSD), 1.6–6.1% for copper (63Cu, 65Cu) and zinc (64Zn, 66Zn) depending on the spot size, the scanning speed, and the element]. Thin section of sheep liver achieved precisions of 27–59% (raster scan) and 9–47% (line scan) RSD for copper, whereas the precision for zinc was significantly better: 8–18% (raster scan) and 4–21% (line scan) RSD. Long line scans and two-dimensional element maps of the thin sections revealed the zonation of copper in sheep liver containing extremely low copper concentrations. Conclusion: Elemental mapping of trace elements generated by LA-ICP-MS can be very precise so that small changes in the elemental concentration in the tissue can be detected and nonuniform spatial distribution of the elements in tissues can be established.

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Hammoudi, A. Hakim, A. H. Benyagoub, C. Benazzouz, C. A. Pineda-Vargas und M. Nkosi. „Compositional Microanalysis of the Obtained Copper Silicide from an Annealed Ternary System Cu/Au/Si by Standard RBS, Microprobe PIXE, XRD and EDS“. Advanced Materials Research 324 (August 2011): 306–9. http://dx.doi.org/10.4028/www.scientific.net/amr.324.306.

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The composition of an annealed ternary system is examined by combined ion beam analysis (standard RBS & nuclear microprobe PIXE), SEM (morphology & EDS) and also with XRD to get the elemental composition and distribution over particular micro regions. The ternary system is built by the superposition of two metal layers, Gold and Copper respectively, both having 1200 Å in thickness, successively deposited on a (111) monocristalline silicon substrate. Then, the whole system is subjected to a vacuum heat treatment (at 400°C during 30 min). The enhanced interdiffusion and the arisen transformations are evidenced [8]. The investigations are particularly, emphasized on the induced Copper Silicide. A mapping of the elemental distribution, over restricted area is provided by micro-PIXE using the method of Dynamic Analysis as well as the corresponding Geo-PIXE II Software package. On the other hand, a special web network likewise is realized by performing several EDS punctual analysis, strictly focused on the formed phase site resulting in a well defined planar zoning of the elemental distribution.

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NAKANO, TAKASHI, KAZUO ARAKAWA, HIDEYUKI SAKURAI, MASATOSHI HASEGAWA, KAZUHISA YUASA, ETSUKO SAITO, HITOSHI TAKAGI et al. „RESEARCH OF DISEASE ONSET MECHANISM BY DETERMINING THE DISTRIBUTION OF INTRACELLULAR TRACE ELEMENTS USING AN IN-AIR MICRO-PIXE ANALYZER SYSTEM“. International Journal of PIXE 16, Nr. 01n02 (Januar 2006): 69–76. http://dx.doi.org/10.1142/s0129083506000824.

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A program was started to create a new medical scientific field, which involves radiation oncology and nuclear medicine, utilizing advanced accelerator and ion beam technology. An in-air micro-PIXE analyzer system, which is among the most important technical aspects of the program, was upgraded to improve the accuracy of elemental mapping for samples with thickness variation in the scope of microbeam scanning. In order to address important bio-medical problems in cancer, the intracellular dynamics of trace elements according to the development mechanism of diseases were studied using this system. This paper outlines the program, showing correction of micro-PIXE elemental map by STIM analysis and the preliminary application results.

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MacRae, Colin M., Nicholas C. Wilson und Joel Brugger. „Quantitative Cathodoluminescence Mapping with Application to a Kalgoorlie Scheelite“. Microscopy and Microanalysis 15, Nr. 3 (22.05.2009): 222–30. http://dx.doi.org/10.1017/s1431927609090308.

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AbstractA method for the analysis of cathodoluminescence spectra is described that enables quantitative trace-element-level distributions to be mapped within minerals and materials. Cathodoluminescence intensities for a number of rare earth elements are determined by Gaussian peak fitting, and these intensities show positive correlation with independently measured concentrations down to parts per million levels. The ability to quantify cathodoluminescence spectra provides a powerful tool to determine both trace element abundances and charge state, while major elemental levels can be determined using more traditional X-ray spectrometry. To illustrate the approach, a scheelite from Kalgoorlie, Western Australia, is hyperspectrally mapped and the cathodoluminescence is calibrated against microanalyses collected using a laser ablation inductively coupled plasma mass spectrometer. Trace element maps show micron scale zoning for the rare earth elements Sm3+, Dy3+, Er3+, and Eu3+/Eu2+. The distribution of Eu2+/Eu3+ suggests that both valences of Eu have been preserved in the scheelite since its crystallization 1.63 billion years ago.

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Bentley, J., E. L. Hall und E. A. Kenik. „Quantitative elemental concentrations by energy-filtered imaging“. Proceedings, annual meeting, Electron Microscopy Society of America 53 (13.08.1995): 268–69. http://dx.doi.org/10.1017/s0424820100137719.

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There is widespread interest in elemental distribution maps produced from energy-filtered core-loss images obtained wim commercial imaging energy-filters and slow-scan charge-coupled device (CCD) cameras on transmission electron microscopes (TEMs). Earlier work on the feasibility of mapping solute segregation in stainless steels by energy-filtered imaging confirmed the utility of jump-ratio images (created by division of a post-edge image by a pre-edge one) for rapid assessments of elemental distributions. The effects of diffraction contrast and thickness variations are largely corrected for in such images. However, quantitative compositional information requires the use of net core-loss intensities following subtraction of an extrapolated background. Such core-loss intensities are influenced by diffraction contrast and thickness variations; corrections for these effects may be necessary for a quantitative interpretation. In the present work, energy-filtered images are treated similarly to quantitative electron energy-loss spectrometry (EELS) data. An image showing number of atoms per unit area, nx, is obtained by dividing the core-loss intensity image, Sx(Δ,β), by the low-loss image, J1(Δ,β), obtained with identical energy window Δ and collection half-angle β, and by the partial ionization cross-section, σx(Δ,β). Further normalization by specimen thickness, t, yields an image showing elemental concentration in atoms per unit volume:

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Materna, Th, J. Jolie und W. Mondelaers. „Mapping elemental distributions of heavy elements using tunable gamma-ray beams“. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 149, Nr. 1-2 (Januar 1999): 141–46. http://dx.doi.org/10.1016/s0168-583x(98)00620-x.

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Angel, Allen, und Kathryn A. Jakes. „Preparation And elemental analysis of ancient fibers“. Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 410–11. http://dx.doi.org/10.1017/s0424820100126846.

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Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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Longo, Paolo, Paul J. Thomas und Ray D. Twesten. „Atomic-Level EELS Mapping Using High-Energy Edges in Dualeels™ Mode“. Microscopy Today 20, Nr. 4 (Juli 2012): 30–36. http://dx.doi.org/10.1017/s1551929512000478.

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With advancements in aberration correction, the spatial resolution of scanning transmission electron microscopy (STEM) has been enormously improved. In addition to the reduction of the STEM probe size, a dramatic increase in the STEM probe current has been realized, leading to the routine acquisition of high-resolution elemental and chemical maps using electron energy loss spectrometry (EELS). Using EELS combined with these advanced STEM instruments, atomic-level resolution information can be obtained from various types of materials, revealing the nature of interfaces, elemental distribution, presence of defects, and much more. In addition to simple elemental composition distributions, EELS is capable of delivering information about the chemical bonding, local atomic coordination, oxidation states, band gaps, and chemical phases of a broad range of materials at the fundamental resolution limit of the property being probed. Atomic-level EELS maps of these fundamental material properties can now be obtained with the acquisition time, to a large extent, limited only by the speed of the EELS spectrometer and not by the signal being measured. The availability of fast EELS spectrometers with large angular collection efficiencies has closed the gap between the rate of signal generation in the specimen and the speed at which this signal can be detected. This significantly increases the amount of information that can be acquired using EELS. Using the most recent generation of spectrometers, EELS data can be acquired at well over 1,000 spectra per second with a high-duty cycle. Fifth-order spectral aberration correction in this generation of spectrometers allows the use of the large collection angles needed to match the increased convergence angle that Cs-probe-corrected systems present, improving collection efficiency while maintaining energy resolution. These advances, when taken together, result in a well matched source/detector system capable of recording high-energy EELS edges at atomic resolution at a rate fast enough to limit electron beam damage to the sample.

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Lyu, Lingyun, Takeshi Hanada, Naohiro Yamahira, Jun Morita, Ryota Yamamoto, Ken Itomi, Takumi Adachi, Sho Kubouchi und Shin Horiuchi. „Spatial distribution of silica fillers in phase‐separated rubber blends investigated by three‐dimensional elemental mapping“. Journal of Applied Polymer Science 138, Nr. 45 (27.07.2021): 51443. http://dx.doi.org/10.1002/app.51443.

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Gueriau, Pierre, Solenn Réguer, Nicolas Leclercq, Camila Cupello, Paulo M. Brito, Clément Jauvion, Séverin Morel, Sylvain Charbonnier, Dominique Thiaudière und Cristian Mocuta. „Visualizing mineralization processes and fossil anatomy using synchronous synchrotron X-ray fluorescence and X-ray diffraction mapping“. Journal of The Royal Society Interface 17, Nr. 169 (August 2020): 20200216. http://dx.doi.org/10.1098/rsif.2020.0216.

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Fossils, including those that occasionally preserve decay-prone soft tissues, are mostly made of minerals. Accessing their chemical composition provides unique insight into their past biology and/or the mechanisms by which they preserve, leading to a series of developments in chemical and elemental imaging. However, the mineral composition of fossils, particularly where soft tissues are preserved, is often only inferred indirectly from elemental data, while X-ray diffraction that specifically provides phase identification received little attention. Here, we show the use of synchrotron radiation to generate not only X-ray fluorescence elemental maps of a fossil, but also mineralogical maps in transmission geometry using a two-dimensional area detector placed behind the fossil. This innovative approach was applied to millimetre-thick cross-sections prepared through three-dimensionally preserved fossils, as well as to compressed fossils. It identifies and maps mineral phases and their distribution at the microscale over centimetre-sized areas, benefitting from the elemental information collected synchronously, and further informs on texture (preferential orientation), crystallite size and local strain. Probing such crystallographic information is instrumental in defining mineralization sequences, reconstructing the fossilization environment and constraining preservation biases. Similarly, this approach could potentially provide new knowledge on other (bio)mineralization processes in environmental sciences. We also illustrate that mineralogical contrasts between fossil tissues and/or the encasing sedimentary matrix can be used to visualize hidden anatomies in fossils.

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Dean, Christopher, Adeline Le Cabec, Kathryn Spiers, Yi Zhang und Jan Garrevoet. „Incremental distribution of strontium and zinc in great ape and fossil hominin cementum using synchrotron X-ray fluorescence mapping“. Journal of The Royal Society Interface 15, Nr. 138 (Januar 2018): 20170626. http://dx.doi.org/10.1098/rsif.2017.0626.

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Cementum and the incremental markings it contains have been widely studied as a means of ageing animals and retrieving information about diet and nutrition. The distribution of trace elements in great ape and fossil hominin cementum has not been studied previously. Synchrotron X-ray fluorescence (SXRF) enables rapid scanning of large tissue areas with high resolution of elemental distributions. First, we used SXRF to map calcium, phosphorus, strontium and zinc distributions in great ape dentine and cementum. At higher resolution, we compared zinc and strontium distributions in cellular and acellular cementum in regions where clear incremental markings were expressed. We then mapped trace element distributions in fossil hominin dentine and cementum from the 1.55–1.65 million year old site of Koobi Fora, Kenya. Zinc, in particular, is a precise marker of cementum increments in great apes, and is retained in fossil hominin cementum, but does not correspond well with the more diffuse fluctuations observed in strontium distribution. Cementum is unusual among mineralized tissues in retaining so much zinc. This is known to reduce the acid solubility of hydroxyapatite and so may confer resistance to resorption by osteoclasts in the dynamic remodelling environment of the periodontal ligament and alveolar bone.

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Bentley, J., J. E. Wittig, J. F. Al-Sharab und N. D. Evans. „Elemental Mapping of Co-Based Magnetic Recording Media: EFTEM and STEM Spectrum Imaging“. Microscopy and Microanalysis 7, S2 (August 2001): 1140–41. http://dx.doi.org/10.1017/s1431927600031779.

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The optimized performance of Co(CrTaPt) thin-film longitudinal magnetic recording media (for computer hard discs) depends critically on the grain size distribution and on intergranular Cr segregation that magnetically isolates the grains. These microstructural aspects of both model and commercial media have been extensively investigated at ∽1 nm resolution with quantitative elemental mapping by energy-filtered transmission electron microscopy (EFTEM) of Cr, Co, and O, but not Ta and Pt which unfortunately are not amenable to quantitative elemental mapping by EFTEM. Procedures for data acquisition and processing have been refined in order to provide robust methods for measuring intergranular compositions for statistically significant numbers of grains. Figure 1 shows results obtained with a Gatan imaging filter (GIF) interfaced to a LaB6 Philips CM30 for a carbon-capped 25-nm-thick film of Co80Cr16Ta4 grown on a Cr underlayer. Typical acquisition parameters have been described previously. to avoid the Cr underlayer, foil thicknesses t<0.2X are used, including the carbon overlayer (λ = inelastic mean free path ≌100 nm).

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INOMATA, K., K. ISHII, H. YAMAZAKI, S. MATSUYAMA, Y. KIKUCHI, Y. WATANABE, A. ISHIZAKI et al. „DEVELOPMENT OF AN IN-AIR ON/OFF AXIS STIM SYSTEM FOR QUANTITATIVE ELEMENTAL MAPPING“. International Journal of PIXE 16, Nr. 03n04 (Januar 2006): 149–56. http://dx.doi.org/10.1142/s0129083506000939.

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We have developed an in-air on/off axis STIM for simultaneous density mapping with PIXE and RBS, which will be useful for damage-monitoring in cell analysis and for yield correction based on the thickness distribution of X-ray self-absorption in samples. The in-air on/off axis STIM system provides a mass concentration map in the cell analysis. In the system, a thin scattering foil is placed downstream of the sample and scattered protons are detected by a Si -PIN photodiode set at 30 degrees with respect to the beam axis. These components are set in a He -gas-filled chamber to reduce energy loss, scattering and sample damage. Using this system, areal density mapping is carried out for RBL-2H3 cells simultaneously with PIXE and RBS. Correction for self-absorption is performed and areal density map of elements is converted into a mass-concentration map using the measured matrix density. The areal density distribution of P corresponds to that of matrix and mass concentration of P is uniform in the cell region. On the other hand, Br is concentrated in the nucleus, even in the mass concentration map. The Br accumulation in the nucleus is first confirmed in mass concentration using the on/off axis STIM and PIXE system. The in-air on/off STIM system will be effective for monitoring changes in cell density during beam irradiation.

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Anné, Jennifer, Nicholas P. Edwards, Roy A. Wogelius, Allison R. Tumarkin-Deratzian, William I. Sellers, Arjen van Veelen, Uwe Bergmann et al. „Synchrotron imaging reveals bone healing and remodelling strategies in extinct and extant vertebrates“. Journal of The Royal Society Interface 11, Nr. 96 (06.07.2014): 20140277. http://dx.doi.org/10.1098/rsif.2014.0277.

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Current understanding of bone healing and remodelling strategies in vertebrates has traditionally relied on morphological observations through the histological analysis of thin sections. However, chemical analysis may also be used in such interpretations, as different elements are known to be absorbed and used by bone for different physiological purposes such as growth and healing. These chemical signatures are beyond the detection limit of most laboratory-based analytical techniques (e.g. scanning electron microscopy). However, synchrotron rapid scanning–X-ray fluorescence (SRS–XRF) is an elemental mapping technique that uniquely combines high sensitivity (ppm), excellent sample resolution (20–100 µm) and the ability to scan large specimens (decimetre scale) approximately 3000 times faster than other mapping techniques. Here, we use SRS–XRF combined with microfocus elemental mapping (2–20 µm) to determine the distribution and concentration of trace elements within pathological and normal bone of both extant and extinct archosaurs ( Cathartes aura and Allosaurus fragilis ). Results reveal discrete chemical inventories within different bone tissue types and preservation modes. Chemical inventories also revealed detail of histological features not observable in thin section, including fine structures within the interface between pathological and normal bone as well as woven texture within pathological tissue.

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YUKAWA, MASAE, YUJI ISHIKAWA, HITOSHI IMASEKI und KAZUKO AOKI. „ELEMENTAL DISTRIBUTION IN ORGANS OF MEDAKA, Oryzias laptipes, BURDENED WITH X-RAY IRRADIATION AND SALTY WATER (Part II)“. International Journal of PIXE 11, Nr. 03n04 (Januar 2001): 119–24. http://dx.doi.org/10.1142/s0129083501000177.

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Balance of essential elements in organisms might be changed by environmental stresses. Small teleost fish, Medaka, was burdened with X-ray irradiation (total dose: 17Gy) and salty water (70% NaCl of sea water). These stresses are not lethal dose. Essential elements in various organs in the fish were measured by PIXE method and compared with a control fish to determine the effect of two types of the burdens on the elemental contents. P, K, Ca and Br are examined in brain, eye, liver, ovary, spleen and intestine. P and K did not change their concentrations with both of the stresses. Ca concentrations increased under both stresses in the brain, eye, liver and spleen, and decreased in the intestine and ovary. Br concentrations of the organs largely changed in the case of salty water breeding. Micro-beam scanning PIXE provided elemental mapping of thin section of Medaka eye with STIM imaging.

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Kawasaki, M., T. Oikawa, K. Ibe, K. H. Park, M. Shiojiri und M. Kersker. „Compositional Characterization of an O-N-O Layer in a Dram Using FE-TEM and Energy Filtered Elemental Mapping“. Microscopy and Microanalysis 4, S2 (Juli 1998): 148–49. http://dx.doi.org/10.1017/s1431927600020869.

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A dielectric O-N-O multi-layer is formed between a single-crystal silicon substrate and a polycrystalline silicon gate to insulate them. The nominal structure of the layer is SiO2-Si3N4-SiO2. In this study, in order to visualize the elemental distribution, energy filtered mapping technique was used and also the relative concentration was calculated from the intensities of the elemental maps to characterize the structure quantitatively.The specimen was cut from a 16M-DRAM device and made suitable for TEM observation by the cross-section ion milling method. The O-N-O layer was examined using a JEM-2010F FE-TEM equipped with a post column energy filter(GIF 200). Fig. 1 shows energy filtered elemental maps of Si, O and N with an elastic image of the O-N-O layer obtained by the three-window method.As a map is produced after a background intensity extrapolated from two pre-edge images is subtracted from a post-edge image, each pixel of these maps provides energy loss intensity of an element.

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Hani, A., E. Pazira, M. Manshouri, S. Babaie Kafaky und M. Ghahroudi Tali. „Spatial distribution and mapping of risk elements pollution in agricultural soils of southern Tehran, Iran“. Plant, Soil and Environment 56, No. 6 (03.06.2010): 288–96. http://dx.doi.org/10.17221/16/2010-pse.

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In order to evaluate risk elements and their spatial distribution in agricultural fields south of Tehran, statistics, geostatistics and geographic information system (GIS) were used. The content of Hg, As, Pb, Mo, and Be were determined in 106 samples. The results showed that primary inputs of As and Hg were due to anthropogenic sources, while Pb, Mo and Be were associated with pedogenic and anthropogenic factors. Ordinary kriging was carried out to map the spatial patterns of risk elements and disjunctive kriging was used to quantify the probability of risk elements concentrations higher than their guide value. The results show that As, Hg, Mo and Be exhibit pollution risk in the study area. The high pollution sources evaluated were related with usage of urban and industrial wastewater for agricultural practice. The results of this study are helpful for risk assessment of environmental pollution for decision making for vegetable production and ecosystem improving.

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El-Hasa, Tayel. „SYNCHROTRON BASED MICRO-MAPPING AND XAFS INVESTIGATION OF Fe-Mn AND EPIGENETIC INTERGROWTH WITHIN THE CAMBRIAN SHALLOW MANGANESE DEPOSITS, SOUTH JORDAN“. Iraqi Geological Journal 53, Nr. 1A (31.01.2020): 117–27. http://dx.doi.org/10.46717//igj.53.1a.r7.2020.01.28.

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The current work investigates the Cambrian Manganese ore deposits from Wadi Dana at central Wadi Araba region. This investigation aims to unravel the chemistry and micro-textures of the mineral paragenetic sequence for these manganese ore deposits. Particularly the Fe–Mn intimate intergrowth micro texture and the epigenetic Mn mineralization associated with Cu minerals. The combination of the synchrotron-based X-ray fluorescence (syn-XRF) micro-mapping and X-ray absorption fine structure (XAFS) techniques were used. They provide a clear picture of the elemental distribution of Mn, Fe, Cu, and Pb and other elements presented within the ore micro textures. Besides, it determines the exact elemental speciation. The results obtained gave a better understanding of the elemental atomic structures and eventually the depositional environment. Particularly, the syn-XRF micro-mapping reveals the existing of many successive evolution stages in the Mn ores. Besides, the X-ray Absorption Near Edge Structure (XANES) results showed that the micro-rhythmic texture is changing from Mn+4 (Pyrolusite) into Fe+3 (Hematite). This is evidence for the role of Eh as the main controlling factor during the ore formation. Eventually, indicating tentatively the paleoceanography setting of the Mn deposits. This is related to the continuous transgression-regression on the sea level in a semi-closed sea.

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Bentley, J., und E. A. Kenik. „Elemental mapping of segregation in stainless steels with an imaging filter“. Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 1000–1001. http://dx.doi.org/10.1017/s0424820100172735.

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Elemental mapping in a TEM equipped with an imaging filter is expected to become an important microanalysis technique in materials science. The efficacy of the technique for studying solute segregation and composition gradients is not as well established as for mapping precipitate distributions. We have therefore undertaken a preliminary investigation of two types of solute segregation in 300-series austenitic stainless steels.Elemental mapping was performed at 200 kV with Gatan Imaging Filters (GIF™) attached to JEM 2010 and Philips CM20 electron microscopes operating with probe currents of > 100 nA. Further work will also use a GIF on a Philips CM30 at ORNL. Images were recorded (exposure times of 15-50 s) with the slow scan CCD camera of the filter for 30- or 40-eV-wide windows before and after ionization edges of interest, including Cr-, Fe-, and Ni-L23 edges (see the spectrum shown in Fig. 1), and were processed with Gatan Digital Micrograph™ software.

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Hendy, E., A. Lanzirotti, T. Rasbury und J. Lough. „Synchrotron μ-XRF mapping of elemental distributions across coral skeleton micro-architecture“. Geochimica et Cosmochimica Acta 70, Nr. 18 (August 2006): A246. http://dx.doi.org/10.1016/j.gca.2006.06.1591.

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