Multiscale 3D Virtual Dissections of 100-Million-Year-Old Flowers Using X-Ray Synchrotron Micro- and Nanotomography

2014 ◽  
Vol 20 (1) ◽  
pp. 305-312 ◽  
Author(s):  
Jean-David Moreau ◽  
Peter Cloetens ◽  
Bernard Gomez ◽  
Véronique Daviero-Gomez ◽  
Didier Néraudeau ◽  
...  

AbstractA multiscale approach combining phase-contrast X-ray micro- and nanotomography is applied for imaging a Cretaceous fossil inflorescence in the resolution range from 0.75 μm to 50 nm. The wide range of scale views provides three-dimensional reconstructions from the external gross morphology of the inflorescence fragment to the finest exine sculptures of in situ pollen. This approach enables most of the characteristics usually observed under light microscopy, or with low magnification under scanning and transmission electron microscopy, to be obtained nondestructively. In contrast to previous tomography studies of fossil and extant flowers that used resolutions down to the micron range, we used voxels with a 50 nm side in local tomography scans. This high level of resolution enables systematic affinities of fossil flowers to be established without breaking or slicing specimens.

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1615
Author(s):  
Qiong Li ◽  
Jürgen Gluch ◽  
Zhongquan Liao ◽  
Juliane Posseckardt ◽  
André Clausner ◽  
...  

Fossil frustules of Ellerbeckia and Melosira were studied using laboratory-based nano X-ray tomography (nano-XCT), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS). Three-dimensional (3D) morphology characterization using nondestructive nano-XCT reveals the continuous connection of fultoportulae, tube processes and protrusions. The study confirms that Ellerbeckia is different from Melosira. Both genera reveal heavily silicified frustules with valve faces linking together and forming cylindrical chains. For this cylindrical architecture of both genera, valve face thickness, mantle wall thickness and copulae thickness change with the cylindrical diameter. Furthermore, EDS reveals that these fossil frustules contain Si and O only, with no other elements in the percentage concentration range. Nanopores with a diameter of approximately 15 nm were detected inside the biosilica of both genera using TEM. In situ micromechanical experiments with uniaxial loading were carried out within the nano-XCT on these fossil frustules to determine the maximal loading force under compression and to describe the fracture behavior. The fracture force of both genera is correlated to the dimension of the fossil frustules. The results from in situ mechanical tests show that the crack initiation starts either at very thin features or at linking structures of the frustules.


Inorganics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 85
Author(s):  
Maryam Golozar ◽  
Raynald Gauvin ◽  
Karim Zaghib

This work summarizes the most commonly used in situ techniques for the study of Li-ion batteries from the micro to the atomic level. In situ analysis has attracted a great deal of interest owing to its ability to provide a wide range of information about the cycling behavior of batteries from the beginning until the end of cycling. The in situ techniques that are covered are: X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Scanning Transmission Electron Microscopy (STEM). An optimized setup is required to be able to use any of these in situ techniques in battery applications. Depending on the type of data required, the available setup, and the type of battery, more than one of these techniques might be needed. This study organizes these techniques from the micro to the atomic level, and shows the types of data that can be obtained using these techniques, their advantages and their challenges, and possible strategies for overcoming these challenges.


2005 ◽  
Vol 20 (7) ◽  
pp. 1860-1868 ◽  
Author(s):  
J.J. Hu ◽  
A.A. Voevodin ◽  
J.S. Zabinski

Yttria-stabilized zirconia (YSZ)-Au composite coatings have great potential as solid film lubricants for aerospace applications over a wide range of environmental conditions. They were grown on steel disks or silicon wafers by pulsed laser ablation of YSZ and simultaneous magnetron sputtering of a Au target. Such a combination of ceramics with soft metals improved the toughness of the composite coating and increased its ability to lubricate at high temperature. Information on the time-dependent response of these microstructures to changes in temperature is essential to tribological investigations of high temperature performance. In situ transmission electron microscopy was used to directly measure the dynamic change of YSZ-Au coating structure at elevated temperatures. High-resolution electron microscopy and electron diffraction showed that amorphous YSZ-5 at.% Au coatings proceeded to crystallize under the irradiation of electron beams. Time varying x-ray energy dispersive spectra measured a loss of oxygen in the sample during about 10 min of irradiation with subsequent slight oxygen recovery. This behavior was related to the activation of oxygen diffusion under electron irradiation. X-ray diffraction patterns from vacuum annealed samples verified crystallization of the coatings at 500 °C. Real-time growth of Au nanograins in the sample was observed as the temperature was increased to 500 °C in a TEM specimen holder that could be heated. The grain growth process was recorded using a charge-coupled device camera installed on the transmission electron microscope. The crystallization and growth of zirconia and Au nanograins resulted in low friction during tribological tests. The nucleation of Au islands on heated ball-on-flat specimens was responsible for lowering friction.


1998 ◽  
Vol 549 ◽  
Author(s):  
C.F. Blanford ◽  
T.N. Do ◽  
B.T. Holland ◽  
A. Stein

AbstractThe facile synthesis of three-dimensional macroporous arrays of titania, zirconia and alumina was recently reported [1]. The synthesis of these materials has now been extended to the oxides of iron, tungsten, and antimony, as well as a mixed yttrium-zirconium system and organically modi- fied silicates. These materials were characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray energy dispersive spectrometry (EDS), and powder X-ray diffraction (XRD). Ordered structures of iron, tungsten, and antimony were formed from alkoxide precursors as in the originally reported synthesis, but the template was removed at a lower temperature. Samples of vinyl- and 2-cyanoethyl-modified silicates were formed from a mixture of organotrialkoxysilane and tetraalkoxysilane precursors; the polystyrene template was removed by extraction with a THF/acetone mixture. These results show the ease of extending the original syn- thesis to a wide range of systems. Also, the ability to form homogenous mixed-metal oxides will be important for tailoring the dielectric and photonic properties of these materials.


2017 ◽  
Vol 24 (1) ◽  
pp. 240-247 ◽  
Author(s):  
M. Álvarez-Murga ◽  
J. P. Perrillat ◽  
Y. Le Godec ◽  
F. Bergame ◽  
J. Philippe ◽  
...  

X-ray tomography is a non-destructive three-dimensional imaging/microanalysis technique selective to a wide range of properties such as density, chemical composition, chemical states and crystallographic structure with extremely high sensitivity and spatial resolution. Here the development of in situ high-pressure high-temperature micro-tomography using a rotating module for the Paris–Edinburgh cell combined with synchrotron radiation is described. By rotating the sample chamber by 360°, the limited angular aperture of ordinary high-pressure cells is surmounted. Such a non-destructive high-resolution probe provides three-dimensional insight on the morphological and structural evolution of crystalline as well as amorphous phases during high pressure and temperature treatment. To demonstrate the potentials of this new experimental technique the compression behavior of a basalt glass is investigated by X-ray absorption tomography, and diffraction/scattering tomography imaging of the structural changes during the polymerization of C60 molecules under pressure is performed. Small size and weight of the loading frame and rotating module means that this apparatus is portable, and can be readily installed on most synchrotron facilities to take advantage of the diversity of three-dimensional imaging techniques available at beamlines. This experimental breakthrough should open new ways for in situ imaging of materials under extreme pressure–temperature–stress conditions, impacting diverse areas in physics, chemistry, geology or materials sciences.


2020 ◽  
Vol 27 (5) ◽  
pp. 1339-1346 ◽  
Author(s):  
Silja Flenner ◽  
Malte Storm ◽  
Adam Kubec ◽  
Elena Longo ◽  
Florian Döring ◽  
...  

Hard X-ray nanotomography enables 3D investigations of a wide range of samples with high resolution (<100 nm) with both synchrotron-based and laboratory-based setups. However, the advantage of synchrotron-based setups is the high flux, enabling time resolution, which cannot be achieved at laboratory sources. Here, the nanotomography setup at the imaging beamline P05 at PETRA III is presented, which offers high time resolution not only in absorption but for the first time also in Zernike phase contrast. Two test samples are used to evaluate the image quality in both contrast modalities based on the quantitative analysis of contrast-to-noise ratio (CNR) and spatial resolution. High-quality scans can be recorded in 15 min and fast scans down to 3 min are also possible without significant loss of image quality. At scan times well below 3 min, the CNR values decrease significantly and classical image-filtering techniques reach their limitation. A machine-learning approach shows promising results, enabling acquisition of a full tomography in only 6 s. Overall, the transmission X-ray microscopy instrument offers high temporal resolution in absorption and Zernike phase contrast, enabling in situ experiments at the beamline.


2020 ◽  
Vol 27 (6) ◽  
pp. 1707-1719 ◽  
Author(s):  
Jasper Frohn ◽  
Diana Pinkert-Leetsch ◽  
Jeannine Missbach-Güntner ◽  
Marius Reichardt ◽  
Markus Osterhoff ◽  
...  

A multiscale three-dimensional (3D) virtual histology approach is presented, based on two configurations of propagation phase-contrast X-ray tomography, which have been implemented in close proximity at the GINIX endstation at the beamline P10/PETRA III (DESY, Hamburg, Germany). This enables the 3D reconstruction of characteristic morphological features of human pancreatic normal and tumor tissue, as obtained from cancer surgery, first in the form of a large-scale overview by parallel-beam illumination, followed by a zoom into a region-of-interest based on zoom tomography using a Kirkpatrick–Baez mirror with additional waveguide optics. To this end 1 mm punch biopsies of the tissue were taken. In the parallel tomography, a volumetric throughput on the order of 0.01 mm3 s−1 was achieved, while maintaining the ability to segment isolated cells. With a continuous rotation during the scan, a total acquisition time of less than 2 min was required for a full tomographic scan. Using the combination of both setups, islets of Langerhans, a three-dimensional cluster of cells in the endocrine part of the pancreas, could be located. Cells in such an islet were segmented and visualized in 3D. Further, morphological alterations of tumorous tissue of the pancreas were characterized. To this end, the anisotropy parameter Ω, based on intensity gradients, was used in order to quantify the presence of collagen fibers within the entire biopsy specimen. This proof-of-concept experiment of the multiscale approach on human pancreatic tissue paves the way for future 3D virtual pathology.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
Yu Liu

The image obtained in a transmission electron microscope is the two-dimensional projection of a three-dimensional (3D) object. The 3D reconstruction of the object can be calculated from a series of projections by back-projection, but this algorithm assumes that the image is linearly related to a line integral of the object function. However, there are two kinds of contrast in electron microscopy, scattering and phase contrast, of which only the latter is linear with the optical density (OD) in the micrograph. Therefore the OD can be used as a measure of the projection only for thin specimens where phase contrast dominates the image. For thick specimens, where scattering contrast predominates, an exponential absorption law holds, and a logarithm of OD must be used. However, for large thicknesses, the simple exponential law might break down due to multiple and inelastic scattering.


Author(s):  
T. Yaguchi ◽  
M. Konno ◽  
T. Kamino ◽  
M. Ogasawara ◽  
K. Kaji ◽  
...  

Abstract A technique for preparation of a pillar shaped sample and its multi-directional observation of the sample using a focused ion beam (FIB) / scanning transmission electron microscopy (STEM) system has been developed. The system employs an FIB/STEM compatible sample rotation holder with a specially designed rotation mechanism, which allows the sample to be rotated 360 degrees [1-3]. This technique was used for the three dimensional (3D) elemental mapping of a contact plug of a Si device in 90 nm technology. A specimen containing a contact plug was shaped to a pillar sample with a cross section of 200 nm x 200 nm and a 5 um length. Elemental analysis was performed with a 200 kV HD-2300 STEM equipped with the EDAX genesis Energy dispersive X-ray spectroscopy (EDX) system. Spectrum imaging combined with multivariate statistical analysis (MSA) [4, 5] was used to enhance the weak X-ray signals of the doped area, which contain a low concentration of As-K. The distributions of elements, especially the dopant As, were successfully enhanced by MSA. The elemental maps were .. reconstructed from the maps.


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