Development of a hard x-ray imaging microscope

Lai, Barry; Yun, Wenbing; Xiao, Yanan; Yang, Luyi; Legnini, D.; Cai, Zhonghou; Krasnoperova, Azalia A.; Cerrina, F.; DiFabrizio, E.; Grella, L.; Gentili, M.

doi:10.1063/1.1145666

Cited by 84 publications

(16 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A number of methods have been developed, most notably one termed 3DXRD at the European Synchrotron radiation facility (ESRF), in collaboration with the Risø National Lab 113 and another at the Applied Photon Source (APS). 114 5 Landmark achievements in focussing for soft Fresnel zone plates (FZPs), 69,[82][83][84][85][86][87][88][89] hard FZPs, 72,[89][90][91][92][93][94] Kirkpatrick-In the former a small, usually letter-box shaped, monochromatic beam is sent through a sample and, as in absorption tomography, the sample is rotated around an axis perpendicular to the beam. Each irradiated grain diffracts part of the incident beam.…”

Section: Crystal Grain Imagingmentioning

confidence: 99%

Quantitative X-ray tomography

Maire¹,

Withers²

2013

International Materials Reviews

1,060

601

View full text Add to dashboard Cite

X-ray computer tomography (CT) is fast becoming an accepted tool within the materials science community for the acquisition of 3D images. Here the authors review the current state of the art as CT transforms from a qualitative diagnostic tool to a quantitative one. Our review considers first the image acquisition process, including the use of iterative reconstruction strategies suited to specific segmentation tasks and emerging methods that provide more insight (e.g. fast and high resolution imaging, crystallite (grain) imaging) than conventional attenuation based tomography. Methods and shortcomings of CT are examined for the quantification of 3D volumetric data to extract key topological parameters such as phase fractions, phase contiguity, and damage levels as well as density variations. As a non-destructive technique, CT is an ideal means of following structural development over time via time lapse sequences of 3D images (sometimes called 3D movies or 4D imaging). This includes information needed to optimise manufacturing processes, for example sintering or solidification, or to highlight the proclivity of specific degradation processes under service conditions, such as intergranular corrosion or fatigue crack growth. Besides the repeated application of static 3D image quantification to track such changes, digital volume correlation (DVC) and particle tracking (PT) methods are enabling the mapping of deformation in 3D over time. Finally the use of CT images is considered as the starting point for numerical modelling based on realistic microstructures, for example to predict flow through porous materials, the crystalline deformation of polycrystalline aggregates or the mechanical properties of composite materials.

show abstract

Section: Crystal Grain Imagingmentioning

confidence: 99%

Quantitative X-ray tomography

Maire¹,

Withers²

2013

International Materials Reviews

1,060

601

View full text Add to dashboard Cite

show abstract

“…Moreover, in synchrotron μ-XRF analysis, the intensity and clarity of the fluorescence depend on the varied beam current intensity of X-ray with scanning time and the differences in size of the beam and the distance between detector and sample (Lai et al 1995). The relative quantitative changes in metals distributed on the samples can be determined if the scan conditions are the same.…”

Section: Discussionmentioning

confidence: 98%

Differential expression of extracellular thiol groups of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on S0 and Fe2+

et al. 2015

View full text Add to dashboard Cite

Bio-oxidation of elemental sulfur (S(0)) is very important in bioleaching and sulfur cycle. S(0) was proposed to be first activated by reacting with reactive thiol groups (-SH) of outer membrane proteins, forming -S n H (n ≥ 2) complexes. The differential expression of -SH of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on Fe(2+) and S(0) was investigated by synchrotron radiation-based scanning transmission X-ray microscopy (STXM) imaging and micro-beam X-ray fluorescence (μ-XRF) mapping. The STXM imaging and μ-XRF mapping of extracellular -SH were based on the analysis of Ca(2+) bound on the cell. By comparing Ca(2+) of the cells with and without labeling by Ca(2+), the distribution and content of thiol groups were obtained. The results showed that, for both S. thermosulfidooxidans and A. manzaensis, the expression of extracellular -SH of S(0)-grown cells was higher than that of Fe(2+)-grown cells. Statistical analysis indicated that the expression of extracellular -SH for S. thermosulfidooxidans and A. manzaensis grown on S(0) was 2.37 times and 2.14 times, respectively, to that on Fe(2+). These results evidently demonstrate that the extracellular thiol groups are most probably involved in elemental sulfur activation and oxidation of the acidophilic sulfur-oxidizing microorganisms.

show abstract

“…The resolution of the presently used detector systems, based on a scintillating screen optically coupled to a CCD camera, is restricted by the scintillator properties, optical light transfer, and charge-coupled device granularity, which impose a practical limit of about 1 mm spatial resolution at detector efficiencies of a few percent (Koch et al, 1998). Different approaches have been proposed for trespassing the micrometer barrier and Fresnel zone plates (Lai et al, 1995) or parabolic compound refractive lenses (Schroer, 2002a), have demonstrated to reach sub-micrometer resolution (0.3 mm) but with sufficient efficiency only at energies well below 20 keV. A recently developed detector, installed at the Materials Science Beamline 4S of the Swiss Light Source, achieves a breakthrough in this respect, satisfying the research requirements that ask for an efficient advance towards the submicron range with high energies.…”

Section: Introductionmentioning

confidence: 99%