High resolution hard X-ray photoemission using synchrotron radiation as an essential tool for characterization of thin solid films

The implementation of 3-Dimensional X-Ray Diffraction (3DXRD) Microscopy at the Advanced Photon Source is described. The technique enables the non-destructive structural characterization of polycrystalline bulk materials and is therefore suitable for in situ studies during thermo-mechanical processing. High energy synchrotron radiation and area detectors are employed. First, a forward modeling approach for the reconstruction of grain boundaries from high resolution diffraction images is described. Second, a high resolution reciprocal space mapping technique of individual grains is presented.

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Three dimensional characterization of laser ablation craters using high resolution X-ray computed tomography

Spectrochimica Acta Part B Atomic Spectroscopy ◽

10.1016/j.sab.2017.11.011 ◽

2018 ◽

Vol 139 ◽

pp. 75-82 ◽

Cited By ~ 4

Author(s):

A.H. Galmed ◽

A. du Plessis ◽

S.G. le Roux ◽

E. Hartnick ◽

H. Von Bergmann ◽

...

Keyword(s):

Computed Tomography ◽

Laser Ablation ◽

High Resolution ◽

Three Dimensional ◽

X Ray ◽

X Ray Computed

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High-resolution characterization of the forbidden Si 200 and Si 222 reflections

Journal of Applied Crystallography ◽

10.1107/s1600576715004732 ◽

2015 ◽

Vol 48 (2) ◽

pp. 528-532 ◽

Cited By ~ 77

Author(s):

Peter Zaumseil

Keyword(s):

High Resolution ◽

Angular Range ◽

Angular Divergence ◽

X Ray Diffraction ◽

Multiple Diffraction ◽

Diffraction Plane ◽

X Ray ◽

Sample Orientation ◽

Plane Sample

The occurrence of the basis-forbidden Si 200 and Si 222 reflections in specular X-ray diffraction ω–2Θ scans is investigated in detail as a function of the in-plane sample orientation Φ. This is done for two different diffractometer types with low and high angular divergence perpendicular to the diffraction plane. It is shown that the reflections appear for well defined conditions as a result of multiple diffraction, and not only do the obtained peaks vary in intensity but additional features like shoulders or even subpeaks may occur within a 2Θ range of about ±2.5°. This has important consequences for the detection and verification of layer peaks in the corresponding angular range.

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Crystallization and preliminary X-ray characterization of the 2,4′-dihydroxyacetophenone dioxygenase fromAlcaligenessp. 4HAP

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x14009649 ◽

2014 ◽

Vol 70 (6) ◽

pp. 823-826 ◽

Cited By ~ 4

Author(s):

G. Beaven ◽

A. Bowyer ◽

P. Erskine ◽

S. P. Wood ◽

A. McCoy ◽

...

Keyword(s):

Synchrotron Radiation ◽

Formic Acid ◽

Molecular Oxygen ◽

Aromatic Ring ◽

Bond Cleavage ◽

Its Sequence ◽

Hydroxybenzoic Acid ◽

X Ray

The enzyme 2,4′-dihydroxyacetophenone dioxygenase (or DAD) catalyses the conversion of 2,4′-dihydroxyacetophenone to 4-hydroxybenzoic acid and formic acid with the incorporation of molecular oxygen. Whilst the vast majority of dioxygenases cleave within the aromatic ring of the substrate, DAD is very unusual in that it is involved in C—C bond cleavage in a substituent of the aromatic ring. There is evidence that the enzyme is a homotetramer of 20.3 kDa subunits each containing nonhaem iron and its sequence suggests that it belongs to the cupin family of dioxygenases. By the use of limited chymotrypsinolysis, the DAD enzyme fromAlcaligenessp. 4HAP has been crystallized in a form that diffracts synchrotron radiation to a resolution of 2.2 Å.

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