The authors would like to thank Matt Reinke and the Alcator C-Mod team for designing, building, and testing HIREXSR. This work was supported by DOE Contract Nos. DE-FC02-99ER54512 and DE-AC02-76CH03073.

<ol>
	<li>Reinke, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=X-ray+imaging+crystal+spectroscopy+for+use+in+plasma+transport+research.">X-ray imaging crystal spectroscopy for use in plasma transport research.</a> Rev. Sci. Instrum. 83 (11), 113504 (2012).</li><li>Hill, K. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+High+Resolution+X-Ray+Imaging+Crystal+Spectrometer+for+Measurement+of+Ion-Temperature+and+Rotation-Velocity+Profiles+in+Fusion+Energy+Research+Plasmas.">Development of a High Resolution X-Ray Imaging Crystal Spectrometer for Measurement of Ion-Temperature and Rotation-Velocity Profiles in Fusion Energy Research Plasmas.</a> Plasma Fusion Res. 2, 1067-1067 (2007).</li><li>Greenwald, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=20+years+of+research+on+the+Alcator+C-Mod+tokamak.">20 years of research on the Alcator C-Mod tokamak.</a> Phys. Plasmas. 21 (11), 110501 (2014).</li><li>Rice, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=X-ray+observations+of+medium+Z+H-+and+He-like+ions+with+satellites+from+C-Mod+tokamak+plasmas.">X-ray observations of medium Z H- and He-like ions with satellites from C-Mod tokamak plasmas.</a> J. Phys. B. 48 (14), 144013 (2015).</li><li>Ince-Cushman, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rotation+studies+in+fusion+plasmas+via+imaging+X-ray+crystal+spectroscopy.">Rotation studies in fusion plasmas via imaging X-ray crystal spectroscopy.</a> Rev. Sci. Instrum. 79, (2008).</li><li>Zachariasen, W. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Theory of X-Ray Diffraction in Crystals. , (2004).</li><li>Johann, H. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Die+Erzeugung+lichtstarker+R&#246;ntgenspektren+mit+Hilfe+von+Konkavkristallen.">Die Erzeugung lichtstarker R&#246;ntgenspektren mit Hilfe von Konkavkristallen.</a> Zeitschrift f&#252;r Physik. 69 (3-4), 185-206 (1931).</li><li>Wang, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calculation+of+the+Johann+error+for+spherically+bent+x-ray+imaging+crystal+spectrometers.">Calculation of the Johann error for spherically bent x-ray imaging crystal spectrometers.</a> Rev. Sci. Instrum. 81 (10), (2010).</li><li>Eikenberry, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PILATUS:+a+two-dimensional+X-ray+detector+for+macromolecular+crystallography.">PILATUS: a two-dimensional X-ray detector for macromolecular crystallography.</a> Nucl. Instr. Meth. Phys. Res. A. 501 (1), 260-266 (2003).</li><li>Howard, N. T., Greenwald, M., Rice, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+impurity+confinement+on+Alcator+C-Mod+using+a+multi-pulse+laser+blow-off+system.">Characterization of impurity confinement on Alcator C-Mod using a multi-pulse laser blow-off system.</a> Rev. Sci. Instrum. 82 (3), 1-6 (2011).</li><li>Rice, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-local+heat+transport,+rotation+reversals+and+up/down+impurity+density+asymmetries+in+Alcator+C-Mod+ohmic+L-mode+plasmas.">Non-local heat transport, rotation reversals and up/down impurity density asymmetries in Alcator C-Mod ohmic L-mode plasmas.</a> Nucl. Fusion. 53, 033004 (2013).</li><li>Reinke, M. L., Podpaly, Y., Gao, C., Science, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Operation and Validation of The HIREXSR Analysis COde MIT-Plasma Science and Fusion Center Alcator C-Mod. , (2013).</li><li>Rosen, A. S., Reinke, M. L., Rice, J. E., Hubbard, A. E., Hughes, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+x-ray+line+ratios+for+electron+temperature+determination+in+tokamak+plasmas.">Validation of x-ray line ratios for electron temperature determination in tokamak plasmas.</a> J. Phys. B. 47 (10), 105701 (2014).</li><li>Delgado-Aparicio, L. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-situ+wavelength+calibration+and+temperature+control+for+the+C-Mod+high-resolution+X-ray+crystal+imaging+spectrometer.">In-situ wavelength calibration and temperature control for the C-Mod high-resolution X-ray crystal imaging spectrometer.</a> Bull. Am. Phys. Soc. 55, (2010).</li></ol>

The authors have nothing to disclose.

Die Daten, die durch diese Technik erzeugt wird, kann in einer breiten Vielzahl von experimentellen Untersuchungen verwendet werden. Ion Temperatur und toroidale Geschwindigkeitsprofile können in einer breiten Palette von Transportstudien verwendet werden, einschließlich Eigenselbsterzeugten Plasmarotation und nicht-lokale perturbative Effekte. Messspektren von injizierten Verunreinigungen durch Laser Abblasen kann auch wichtige Informationen über den Transport von Verunreinigungen im Plasma zur Verfügung stellen, w...

Röntgenspektren eine Fülle von Informationen über Hochtemperaturplasmen bereitzustellen; zum Beispiel Elektronentemperatur und Dichte kann aus der Leitung Intensitätsverhältnisse abgeleitet werden. Durch die Verwendung eines Spektrometers Johann Betrachtung des Plasmas außeraxialen ist es möglich , Profile der Plasmaparameter zu konstruieren , wie Dichte, Temperatur und Geschwindigkeit innerhalb des Plasmas mit hoher räumlicher und zeitlicher Auflösung 1,2. Dieses Manuskript stellt den Betrieb des hochauflösenden Röntgenkristall Imaging Spectrometer mit Räumliche Auflösung (HIREXSR), eine hohe Wellenlängenauflösung räumlich Röntgenspektrometer Bildgebung verwendet Wasserstoff- und Helium-ähnliche Ionen mittlerer Ordnungszahl Elemente in einem Tokamak zu sehen Plasma. HIREXSR auf Alcator C-Mod im Einsatz, ein Tokamak-Fusionsgerät mit einem größeren und kleineren Radius von 0,67 m und 0,22 m jeweils. Es arbeitet typischerweise mit Deuterium Plasmen ~ 2 sec mit durchschnittlichen Dichten zwischen 0,2 bis 8,0 x 10 20 m dauerhafte -3 </sup&gt; und zentrale Elektronentemperaturen zwischen 1-9 keV 3. Unter diesen Bedingungen werden mit mittlerer bis hoher Z Störelemente hoch ionisiert und im Röntgenbereich strahlen, die Maßnahmen HIREXSR. Benchmarking Atom Code Modellierung von Röntgenspektren von gut diagnostiziert Laborplasmen erhalten ist wichtig , den Einsatz solcher Spektren zu rechtfertigen Plasmaparameter zu bestimmen , wann eine andere unabhängige Diagnose 4 nicht verfügbar sind. Jedes Spektrometer ist für seine gewünschte Verwendung gebaut. Dementsprechend ist eine allgemeine Beschreibung über die Maschine und die damit verbundenen Konzepte notwendig , um voll und ganz diese leistungsstarken Tools 5 verstehen. Bragg - Reflexion tritt auf, wenn ein Photon benachbarten Schichten eines Kristalls reflektiert wird und eine Strecke , die ein Vielfaches der Wellenlänge ist. Figur 1 veranschaulicht dieses Phänomen. Dieser Zustand wird durch die Gleichung n &amp; lgr; = 2 d sin θ b ausgedrückt, wobei n die Reihenfolge der Wieder istflection, λ die Wellenlänge des Photons ist, d der Abstand zwischen benachbarten Schichten des Kristalls und θ b der Braggsche Winkel ist . Eins - zu - Eins - Entsprechung zwischen λ und θ b zeigt an, dass alle Photonen an einem bestimmten Punkt der Detektorebene Reise mit der gleichen Wellenlänge. jedoch Absorptions- und Präzision Einschränkungen manifest als Abweichung vom Bragg-Winkel in der Praxis. Dadurch ergibt sich nur ein kleiner Bereich von Winkeln , die erhebliche konstruktive Interferenz erzeugen, durch eine Rocking - Kurve 6 dargestellt. Figur 2 ist ein Beispiel für eine Kurve Calcit - Kristall. HIREXSR ist ein Johann - Spektrometer mit einer sphärisch gebogenen Kristall 7. Vor der Beschreibung dieser Art von Gerät, eine Diskussion über eine einfachere, Kreis Spektrometer geeignet ist. Diese Einrichtung besteht aus einem gebogenen Kristall, der einfallenden Photonen reflektiert an ihren jeweiligen Bragg-Winkeln zuwehrt eine Reihe von einzelnen Röntgenphotonenzählung Pixeldetektoren. Der Kristall und dem Detektor liegen tangential zu dem Rowland - Kreis, wie in Figur 3 dargestellt. Der Durchmesser des Rowland - Kreises zu dem Krümmungsradius des Kristalls entspricht. Alle Strahlen, die von einem gegebenen Punkt auf dem Umfang auf einen beliebigen Punkt auf dem Kristall haben denselben Einfallswinkel in bezug auf den Kristall selbst. . Im Falle von HIREXSR eine sphärisch gebogene Kristall ermöglicht räumliche Auflösung in der meridionalen Ebene, dargestellt in Abbildung 4 der meridionalen Fokus f m definiert ist als: f m = R c sin θ b, wobei R c ist der Krümmungsradius Kristall. Die sagittale Brennpunkt f s ist definiert als: f s = - f m / cos 2 θ b. Die räumliche Auflösung des Spektrometers Δ x gegeben istdurch: <img alt="Gleichung" src="/files/ftp_upload/54408/54408eq_DELTA_x.jpg" /> , Wobei L cp ist der Abstand zwischen dem Kristall und dem Plasma, und d ist die Höhe des Kristalls. Weil die 2-dimensionalen Abstand der Kristallschichten diskret ist, muss dies berücksichtigt werden, wenn ein Material der Wahl. Da die Detektorflächen planar sind, können sie nur an einem Punkt tangential zu dem Rowland-Kreis sein, was folglich Anlass zu Fehler gibt, da die erfassten Strahlen nicht genau auf die entsprechenden Punkte auf dem Rowland-Kreis landen. Physikalisch manifestiert diese Fehlausrichtung als &quot;Verschmieren&quot; von Photonen spezifischer Energie auf den Detektor. Dieser Johann Fehler ist definiert als <img alt="Gleichung" src="/files/ftp_upload/54408/54408eq_delta_xj.jpg" /> , Wobei L die Breite des Kristalls. Wenn der Detektor Pixelbreite &amp; Delta; x p viel größer als der Johann Fehler, so wird die spektrale Auflösung ist unabhängig davon. Wenn sie einere vergleichbarer Größe, so kann der Gesamtfehler durch angenähert werden <img alt="Gleichung" src="/files/ftp_upload/54408/54408eq_delta_x_2.jpg" /> . Das Auflösungsvermögen des Kristallspektrometers ist gegeben durch: <img alt="Gleichung" src="/files/ftp_upload/54408/54408eq_lambda0.jpg" /> , woher <img alt="Gleichung" src="/files/ftp_upload/54408/54408eq_delta_theta.jpg" /> . Anstelle des Detektors Tangente an einem Punkt auf dem Rowland - Kreis jedoch Platzierung in HIREXSR der Detektor abgewinkelt ist leicht für die spektrale Entfernungsgenauigkeit zu opfern, wie es in 5 gezeigt ist . Diese Fehleranalyse experimentell verifiziert wurde und entspricht der Erwartung 8. Es gibt zwei entscheidende Parameter zu berücksichtigen, wenn eine Johann-Spektrometer zu entwerfen. Zuerst bestimmt der Abbildungsbereich, was das Spektrometer beobachtet wird. Zur Untersuchung Plasmen, ist es sehr wünschenswert, den gesamten Querschnitt, um zwischen Linienverschiebungen verursacht durch poloidale und Toroi zu unterscheiden anzuzeigendal Rotation. HIREXSR so angebracht ist, dass es das gesamte Plasma anzeigen kann, und geneigt ist leicht außeraxialen von ~ 8 ° (dargestellt in 6) für genaue Messungen Toroid zu ermöglichen. Zweitens regelt Zeitauflösung die minimale Zeit zwischen den Ereignissen, die das Spektrometer aufzeichnen kann. Für Alcator C-Mod, wünschenswerte Werte unterhalb von 20 msec, kürzer ist als die Energie und die Partikeleinschlusszeiten. Die Röntgen Zählpixel Detektoren , die HIREXSR verwendet eine Zeitauflösung von 6 bis 20 ms oder größer 9 unterstützen können. In Tabelle 1 sind alle Modulspezifikationen. Für perturbative Plasma - Studien wird der Laser blow-off - System auf Alcator C-Mod verwendet , um mehrere Ablationen mit präzisem Timing 10 liefern. Der Laser ist ein Nd: YAG (Neodym-dotierter Yttrium-Aluminium-Granat), der bei bis zu 10 Hz. Der Laser trifft auf einem ferngesteuerten optischen Zug , wie in 7 gezeigt , die konzentriert und Stierender Strahl an die gewünschte Stelle auf der Folie. Spotgrößen des Lasers müssen gesteuert werden, damit die Injektion nicht das Plasma zu stören. Eine lange Brennweite (1.146 mm) Sammellinse entlang der optischen Achse über einen ferngesteuerten Lineartisch übersetzt abgetragenen Punktgrößen zu ermöglichen, von ~ 0,5 bis 7 mm variieren. Schnelle Strahllenkung wird über einen 2D-piezoelektrischen Spiegel erreicht. Dieses piezoelektrische System ist mit einem RS232 angetriebenen Spiegel montiert-Befestigung. Neben dem Nd: YAG-Laser, ein 633 nm-Diodenlaser verwendet, um den Standort der Haupt (Infrarot) Strahl anzuzeigen. Die Strahlen werden gebildet durch den ersten Spiegel zu kollinear.

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applying x-ray imaging crystal spectroscopy for use as a high temperature plasma diagnostic

Röntgenspektren eine Fülle von Informationen über Hochtemperaturplasmen bereitzustellen; zum Beispiel Elektronentemperatur und Dichte kann aus der Leitung Intensitätsverhältnisse abgeleitet werden. Durch die Verwendung des Plasma eines Spektrometers Johann Betrachtung ist es möglich, Profile der Plasmaparameter zu konstruieren, wie Dichte, der Temperatur und der Geschwindigkeit, mit guten räumlichen und zeitlichen Auflösung. Allerdings ist das Benchmarking Atom Code Modellierung von Röntgenspektren von gut diagnostiziert Laborplasmen erhalten wichtige Verwendung solcher Spektren zu rechtfertigen Plasmaparameter zu bestimmen, wann eine andere unabhängige Diagnose nicht verfügbar sind. Dieses Manuskript stellt den Betrieb des hochauflösenden Röntgenkristall Imaging Spectrometer mit Räumliche Auflösung (HIREXSR), eine hohe Wellenlängenauflösung räumlich Röntgenspektrometer Bildgebung verwendet Wasserstoff- und Helium-ähnliche Ionen mittlerer Ordnungszahl Elemente in einem Tokamak zu sehen Plasma. Darüber hinaus umfasst das Manuskript einen Laser Abblassystem, die solche Ionen einführenan das Plasma mit präzisem Timing für störungstheoretische Studien von Transport im Plasma zu ermöglichen.

Eine repräsentative Datenprobe aus dem Pixeldetektor für einen Zeit bin für das He-Spektrum wie Argon in 17 gezeigt ist. Die Spektrallinien, gebogen in eine elliptische Form , die durch den kugelförmigen Kristall, sind deutlich sichtbar. Der obere Detektor hat eine gebrochene Detektor-Panel, und es gibt einige tote Pixel über alle Detektoren verstreut. Die Daten aus dem zerbrochenen Detektor-Panel sollte ignoriert werden. Scheiben von dem Detektor die gemessenen Spe...

Watch this Scientific Journal Video about Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic at JoVE.com

Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic

Röntgenspektren bieten eine Fülle von Informationen über Hochtemperaturplasmen. Diese Handschrift stellt den Betrieb einer hohen Wellenlängenauflösung räumlich Röntgenspektrometer Bildgebung verwendet wasserstoff- und Helium artigen Ionen mittlerer Ordnungszahl Elemente in einem Tokamak Plasma anzuzeigen.

Anwenden von Röntgen Imaging Kristall Spektroskopie für den Einsatz als Hochtemperatur-Plasmadiagnose

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line ...

The overall goal of this X-ray spectroscopy technique is to measure the time evolution of the spacial profiles of several plasma parameters, such as ion temperature, rotation velocity, electron temperature, and impurity density in a fusion plasma.This method can help answer key questions in the field of plasma physics by providing experimental data on momentum, heat, and particle transport.This information is then used in transport modeling codes to validate our understanding of the underlying processes.The main advantage of this technique is that it's passive.Demonstrating this procedure will be grad student Norman Cao and undergrad Andr

applying-x-ray-imaging-crystal-spectroscopy-for-use-as-high

Research

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Engineering

11.2K Aufrufe.  Massachusetts Institute of Technology. The overall goal of this X-ray spectroscopy technique is to measure the time evolution of the spacial profiles of several plasma parameters, such as ion temperature, rotation velocity, electron temperature, and impurity density in a fusion plasma.This method can help answer key questions in the field of plasma physics by providing experimental data on momentum, heat, and particle transport.This information is then used in transport modeling codes to validate our understanding of the underlyin...

Serie: Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic

Reservoir Condition Pore-scale Imaging of Multiple Fluid Phases Using X-ray Microtomography

X-ray microtomography was used to image, at a resolution of 6.6 &#181;m, the pore-scale arrangement of residual carbon dioxide ganglia in the pore-space of a carbonate rock at pressures and temperatures representative of typical formations used for CO2 storage. Chemical equilibrium between the CO2, brine and rock phases was maintained using a high pressure high temperature reactor, replicating conditions far away from the injection site. Fluid flow was controlled using high pressure high temperature syringe pumps. To maintain representative in-situ conditions within the micro-CT scanner a carbon fiber high pressure micro-CT coreholder was used. Diffusive CO2 exchange across the confining sleeve from the pore-space of the rock to the confining fluid was prevented by surrounding the core with a triple wrap of aluminum foil. Reconstructed brine contrast was modeled using a polychromatic x-ray source, and brine composition was chosen to maximize the three phase contrast between the two fluids and the rock. Flexible flow lines were used to reduce forces on the sample during image acquisition, potentially causing unwanted sample motion, a major shortcoming in previous techniques. An internal thermocouple, placed directly adjacent to the rock core, coupled with an external flexible heating wrap and a PID controller was used to maintain a constant temperature within the flow cell. Substantial amounts of CO2 were trapped, with a residual saturation of 0.203 &#177; 0.013, and the sizes of larger volume ganglia obey power law distributions, consistent with percolation theory.

We present a methodology for the imaging of multiple fluid phases at reservoir conditions by the use of x-ray microtomography. We show some representative results of capillary trapping in a carbonate rock sample.

Reservoir Zustand Pore angelegte Imaging von mehreren fluiden Phasen Mit Hilfe der Röntgenmikrotomographie

X-ray microtomography was used to image, at a resolution of 6.6 &#181;m, the pore-scale arrangement of residual carbon dioxide ganglia in the pore-space ...

Forschung

Ingenieurwesen

Energy Dispersive X-ray Tomography for 3D Elemental Mapping of Individual Nanoparticles

Energy dispersive X-ray spectroscopy within the scanning transmission electron microscope (STEM) provides accurate elemental analysis with high spatial resolution, and is even capable of providing atomically resolved elemental maps. In this technique, a highly focused electron beam is incident upon a thin sample and the energy of emitted X-rays is measured in order to determine the atomic species of material within the beam path. This elementally sensitive spectroscopy technique can be extended to three dimensional tomographic imaging by acquiring multiple spectrum images with the sample tilted along an axis perpendicular to the electron beam direction.
Elemental distributions within single nanoparticles are often important for determining their optical, catalytic and magnetic properties. Techniques such as X-ray tomography and slice and view energy dispersive X-ray mapping in the scanning electron microscope provide elementally sensitive three dimensional imaging but are typically limited to spatial resolutions of &gt; 20 nm. Atom probe tomography provides near atomic resolution but preparing nanoparticle samples for atom probe analysis is often challenging. Thus, elementally sensitive techniques applied within the scanning transmission electron microscope are uniquely placed to study elemental distributions within nanoparticles of dimensions 10-100 nm.
Here, energy dispersive X-ray (EDX) spectroscopy within the STEM is applied to investigate the distribution of elements in single AgAu nanoparticles. The surface segregation of both Ag and Au, at different nanoparticle compositions, has been observed.

The use of energy dispersive X-ray tomography in the scanning transmission electron microscope to characterize elemental distributions within single nanoparticles in three dimensions is described.

Energieröntgentomografie für 3D-Elementar Zuordnung einzelner Nanopartikel

Energy dispersive X-ray spectroscopy within the scanning transmission electron microscope (STEM) provides accurate elemental analysis with high spatial ...

Failure Analysis of Batteries Using Synchrotron-based Hard X-ray Microtomography

Imaging morphological changes that occur during the lifetime of rechargeable batteries is necessary to understand how these devices fail. Since the advent of lithium-ion batteries, researchers have known that the lithium metal anode has the highest theoretical energy density of any anode material. However, rechargeable batteries containing a lithium metal anode are not widely used in consumer products because the growth of lithium dendrites from the anode upon charging of the battery causes premature cell failure by short circuit. Lithium dendrites can also form in commercial lithium-ion batteries with graphite anodes if they are improperly charged. We demonstrate that lithium dendrite growth can be studied using synchrotron-based hard X-ray microtomography. This non-destructive imaging technique allows researchers to study the growth of lithium dendrites, in addition to other morphological changes inside batteries, and subsequently develop methods to extend battery life.

Synchrotron-based hard X-ray microtomography is used to image the electrochemical growth of dendrites from a lithium metal electrode through a solid polymer electrolyte membrane.

Fehleranalyse von Batterien unter Verwendung Synchrotron-basierte Feströntgenmikrotomographie

Imaging morphological changes that occur during the lifetime of rechargeable batteries is necessary to understand how these devices fail. Since the advent ...

Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating

A procedure for a technique to measure the transverse coherence of synchrotron radiation X-ray sources using a single phase grating interferometer is reported. The measurements were demonstrated at the 1-BM bending magnet beamline of the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). By using a 2-D checkerboard &#960;/2 phase-shift grating, transverse coherence lengths were obtained along the vertical and horizontal directions as well as along the 45&#176; and 135&#176; directions to the horizontal direction. Following the technical details specified in this paper, interferograms were measured at different positions downstream of the phase grating along the beam propagation direction. Visibility values of each interferogram were extracted from analyzing harmonic peaks in its Fourier Transformed image. Consequently, the coherence length along each direction can be extracted from the evolution of visibility as a function of the grating-to-detector distance. The simultaneous measurement of coherence lengths in four directions helped identify the elliptical shape of the coherence area of the Gaussian-shaped X-ray source. The reported technique for multiple-direction coherence characterization is important for selecting the appropriate sample size and orientation as well as for correcting the partial coherence effects in coherence scattering experiments. This technique can also be applied for assessing coherence preserving capabilities of X-ray optics.

The measurement protocol and data analysis procedure are given for obtaining transverse coherence of a synchrotron radiation X-ray source along four directions simultaneously using a single 2-D checkerboard phase grating. This simple technique can be applied for complete transverse coherence characterization of X-ray sources and X-ray optics.

Messung der Röntgenstrahl Coherence entlang mehreren Richtungen unter Verwendung von 2-D-Schachbrett Phase Grating

A procedure for a technique to measure the transverse coherence of synchrotron radiation X-ray sources using a single phase grating interferometer is ...

Use of a Multi-compartment Dynamic Single Enzyme Phantom for Studies of Hyperpolarized Magnetic Resonance Agents

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due to fundamental constraints imposed by the hyperpolarized state, exotic imaging and reconstruction techniques are commonly used. A practical system for characterization of dynamic, multi-spectral imaging methods is critically needed. Such a system must reproducibly recapitulate the relevant chemical dynamics of normal and pathological tissues. The most widely utilized substrate to date is hyperpolarized [1-13C]-pyruvate for assessment of cancer metabolism. We describe an enzyme-based phantom system that mediates the conversion of pyruvate to lactate. The reaction is initiated by injection of the hyperpolarized agent into multiple chambers within the phantom, each of which contains varying concentrations of reagents that control the reaction rate. Multiple compartments are necessary to ensure that imaging sequences faithfully capture the spatial and metabolic heterogeneity of tissue. This system will aid the development and validation of advanced imaging strategies by providing chemical dynamics that are not available from conventional phantoms, as well as control and reproducibility that is not possible in vivo.

A multi-compartment dynamic phantom is used to simulate some biology of interest for metabolic studies using hyperpolarized magnet resonance agents.

Die Verwendung eines Mehrfach Dynamische einzelner Enzym-Phantom für Studien von hyperpolarisiertem Magnetic Resonance Agents

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due ...

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic electrolyte, and an O2-breathing cathode. The aprotic electrolyte is a solution of lithium salt with aprotic solvent; and porous carbon is commonly used as the cathode substrate. To improve the performance, an electrocatalyst is deposited onto the porous carbon substrate by certain deposition methods, such as atomic layer deposition (ALD) and wet-chemistry reaction. The as-prepared cathode materials are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray absorption near edge structure (XANES). A Swagelok-type cell, sealed in a glass chamber filled with pure O2, is used for the electrochemical test on a battery test system. The cells are tested under either capacity-controlled mode or voltage controlled mode. The reaction products are investigated by electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and Raman spectroscopy to study the possible pathway of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). This protocol demonstrates a systematic and efficient arrangement of routine tests of the aprotic Li-O2 battery, including the electrochemical test and characterization of battery materials.

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

A protocol for the electrochemical testing of an aprotic Li-O2 battery with the preparation of electrodes and electrolytes and an introduction of the frequently used methods of characterization is presented here.

Protokoll der elektrochemischen Prüfung und Charakterisierung von aprotische Li-O<sub&gt; 2</sub&gt; Batterie

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic ...

Dynamic Pore-scale Reservoir-condition Imaging of Reaction in Carbonates Using Synchrotron Fast Tomography

Underground storage permanence is a major concern for carbon capture and storage. Pumping CO2 into carbonate reservoirs has the potential to dissolve geologic seals and allow CO2 to escape. However, the dissolution processes at reservoir conditions are poorly understood. Thus, time-resolved experiments are needed to observe and predict the nature and rate of dissolution at the pore scale. Synchrotron fast tomography is a method of taking high-resolution time-resolved images of complex pore structures much more quickly than traditional &#181;-CT. The Diamond Lightsource Pink Beam was used to dynamically image dissolution of limestone in the presence of CO2-saturated brine at reservoir conditions. 100 scans were taken at a 6.1 &#181;m resolution over a period of 2 hours. The images were segmented and the porosity and permeability were measured using image analysis and network extraction. Porosity increased uniformly along the length of the sample; however, the rate of increase of both porosity and permeability slowed at later times.

Synchrotron fast tomography was used to dynamically image dissolution of limestone in the presence of CO2-saturated brine at reservoir conditions. 100 scans were taken at a 6.1 &#181;m resolution over a period of 2 h.

Dynamische Pore-Skala Reservoir-Zustand Abbildung von Reaktions in Karbonate mit Synchrotronstrahlung Schnelle Tomography

Underground storage permanence is a major concern for carbon capture and storage. Pumping CO2 into carbonate reservoirs has the potential to dissolve ...

Adsorption Device Based on a Langatate Crystal Microbalance for High Temperature High Pressure Gas Adsorption in Zeolite H-ZSM-5

We present a high-temperature and high-pressure gas adsorption measurement device based on a high-frequency oscillating microbalance (5 MHz langatate crystal microbalance, LCM) and its use for gas adsorption measurements in zeolite H-ZSM-5. Prior to the adsorption measurements, zeolite H-ZSM-5 crystals were synthesized on the gold electrode in the center of the LCM, without covering the connection points of the gold electrodes to the oscillator, by the steam-assisted crystallization (SAC) method, so that the zeolite crystals remain attached to the oscillating microbalance while keeping good electroconductivity of the LCM during the adsorption measurements. Compared to a conventional quartz crystal microbalance (QCM) which is limited to temperatures below 80 &#176;C, the LCM can realize the adsorption measurements in principle at temperatures as high as 200-300 &#176;C (i.e., at or close to the reaction temperature of the target application of one-stage DME synthesis from the synthesis gas), owing to the absence of crystalline-phase transitions up to its melting point (1,470 &#176;C). The system was applied to investigate the adsorption of CO2, H2O, methanol and dimethyl ether (DME), each in the gas phase, on zeolite H-ZSM-5 in the temperature and pressure range of 50-150 &#176;C and 0-18 bar, respectively. The results showed that the adsorption isotherms of these gases in H-ZSM-5 can be well fitted by Langmuir-type adsorption isotherms. Furthermore, the determined adsorption parameters, i.e., adsorption capacities, adsorption enthalpies, and adsorption entropies, compare well to literature data. In this work, the results for CO2 are shown as an example.

A protocol for high-temperature and high-pressure gas adsorption measurements on zeolite H-ZSM-5 using an adsorption measurement device based on a langatate crystal microbalance is presented. Prior to the adsorption measurements, the synthesis of zeolite H-ZSM-5 on the langatate crystal microbalance sensor by the steam-assisted crystallization (SAC) method is demonstrated.

Adsorptionsvorrichtung Basierend auf einem Langatate Crystal Micro für Hochtemperatur-Hochdruck-Gas Adsorption in Zeolith H-ZSM-5

We present a high-temperature and high-pressure gas adsorption measurement device based on a high-frequency oscillating microbalance (5 MHz langatate ...

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) scaffolds with tunable specific surface areas up to 80 m2&#183;g-1. An aqueous solution of a zirconium salt, yttrium salt, and glucose is mixed with propylene oxide (PO) to form a gel. The gel is dried under ambient conditions to form a xerogel. The xerogel is pressed into pellets and then sintered in an argon atmosphere. During sintering, a YSZ ceramic phase forms and the organic components decompose, leaving behind amorphous carbon. The carbon formed in situ serves as a hard template, preserving a high surface area YSZ nanomorphology at sintering temperature. The carbon is subsequently removed by oxidation in air at low temperature, resulting in a porous, nanostructured YSZ scaffold. The concentration of the carbon template and the final scaffold surface area can be systematically tuned by varying the glucose concentration in the gel synthesis. The carbon template concentration was quantified using thermogravimetric analysis (TGA), the surface area and pore size distribution was determined by physical adsorption measurements, and the morphology was characterized using scanning electron microscopy (SEM). Phase purity and crystallite size was determined using X-ray diffraction (XRD). This fabrication approach provides a novel, flexible platform for realizing unprecedented scaffold surface areas and nanomorphologies for ceramic-based electrochemical energy conversion applications, e.g. solid oxide fuel cell (SOFC) electrodes.

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

A protocol for fabricating porous, nanostructured yttria-stabilized-zirconia (YSZ) scaffolds at temperatures between 1,000 &#176;C and 1,400 &#176;C is presented.

Hochtemperatur Herstellung von Nanostrukturierte Yttrium-stabilisiertes Zirkonoxid (YSZ) Scaffolds durch<em&gt; In Situ</em&gt; Carbon-Templating Xerogele

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...

Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples

In this report, we describe a detailed procedure for acquiring and processing&#160;x-ray microfluorescence (&#956;XRF), and Laue and powder microdiffraction two-dimensional (2D) maps at beamline 12.3.2 of the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory. Measurements can be performed on any sample that is less than 10 cm x 10 cm x 5 cm, with a flat exposed surface. The experimental geometry is calibrated using standard materials (elemental standards for XRF, and crystalline samples such as Si, quartz, or Al2O3 for diffraction). Samples are aligned to the focal point of the x-ray microbeam, and raster scans are performed, where each pixel of a map corresponds to one measurement, e.g., one XRF spectrum or one diffraction pattern. The data are then processed using the in-house developed software XMAS, which outputs text files, where each row corresponds to a pixel position. Representative data from moissanite and an olive snail shell are presented to demonstrate data quality, collection, and analysis strategies.

We describe a beamline setup meant to carry out rapid two-dimensional x-ray fluorescence and x-ray microdiffraction mapping of single crystal or powder samples using either Laue (polychromatic radiation) or powder (monochromatic radiation) diffraction. The resulting maps give information about strain, orientation, phase distribution, and plastic deformation.