Search Results

You searched for all publications:

with publication states 'Published (Approved)'

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

Exact matches
Related results

4 items found (0 items not approved), displaying all items.1

Instruments / Technical Area	Publication Details	Published
I13-2-Diamond Manchester Imaging	Simultaneous heating and compression of irradiated graphite during synchrotron microtomographic imaging A. J. Bodey , Z. Mileeva , T. Lowe , E. Williamson-Brown , D. S. Eastwood , C. Simpson , V. Titarenko , A. N. Jones , Ch. Rau , P. M. Mummery Journal Of Physics: Conference Series 849 X-Ray Microscopy Conference 2016 (XRM 2016) DOI: 10.1088/1742-6596/849/1/012021 Diamond Proposal Number(s): [12200] Open Access Show Abstract ▼ Abstract: Nuclear graphite is used as a neutron moderator in fission power stations. To investigate the microstructural changes that occur during such use, it has been studied for the first time by X-ray microtomography with in situ heating and compression. This experiment was the first to involve simultaneous heating and mechanical loading of radioactive samples at Diamond Light Source, and represented the first study of radioactive materials at the Diamond-Manchester Imaging Branchline I13-2. Engineering methods and safety protocols were developed to ensure the safe containment of irradiated graphite as it was simultaneously compressed to 450N in a Deben 10kN Open-Frame Rig and heated to 300°C with dual focused infrared lamps. Central to safe containment was a double containment vessel which prevented escape of airborne particulates while enabling compression via a moveable ram and the transmission of infrared light to the sample. Temperature measurements were made in situ via thermocouple readout. During heating and compression, samples were simultaneously rotated and imaged with polychromatic X-rays. The resulting microtomograms are being studied via digital volume correlation to provide insights into how thermal expansion coefficients and microstructure are affected by irradiation history, load and heat. Such information will be key to improving the accuracy of graphite degradation models which inform safety margins at power stations.	Jun 2017
I12-JEEP: Joint Engineering, Environmental and Processing	Analytical formula for two-dimensional ring artefact suppression Valeriy Titarenko Journal Of Synchrotron Radiation 23, 1447 - 1461 DOI: 10.1107/S160057751601479X Show Abstract ▼ Abstract: Ring artefacts are the most disturbing artefacts when reconstructed volumes are segmented. A lot of effort has already been put into better X-ray optics, scintillators and detectors in order to minimize the appearance of these artefacts. However, additional processing is often required after standard flat-field correction. Several methods exist to suppress artefacts. One group of methods is based on minimization of the Tikhonov functional. An analytical formula for processing of a single sinogram was developed. In this paper a similar approach is used and a formula for processing two-dimensional projections is found. Thus suppression of ring artefacts is organized as a two-dimensional convolution of `averaged' projections with a given filter. Several approaches are discussed in order to find elements of the filter in a faster and accurate way. Examples of experimental datasets processed by the proposed method are considered.	Nov 2016
B16-Test Beamline	Suppression of ring artefacts when tomographing anisotropically attenuating samples Sofya Titarenko , Valeriy Titarenko , Albrecht Kyrieleis , Philip J. Withers , Francesco De Carlo Journal Of Synchrotron Radiation 18 (3), 427-435 DOI: 10.1107/S0909049511006005 PMID: 21525651 Show Abstract ▼ Abstract: There are many objects for which the attenuation varies significantly as they are rotated during computerized X-ray tomography, for example plate samples. This can lead to significant ring artefacts in the subsequent tomographic reconstructions. In this paper a new method is presented that can successfully suppress such ring artefacts and is applicable to both parallel and cone-beam geometries. Rapid correction is achieved via an analytical formula which involves only a matrix-vector multiplication, for which the matrix is known and depends on a regularization parameter. The efficacy of the method is demonstrated for a paleontological sample (calcified shark cartilage) and a carbon-carbon composite/Ti-SiC metal matrix composite test sample.	Apr 2011
B16-Test Beamline	Region-of-interest tomography using filtered backprojection: assessing the practical limits Albrecht Kyrieleis , Valeriy Titarenko , Thomas Connolley , Mark Ibison , Philip Withers Journal Of Microscopy DOI: 10.1111/j.1365-2818.2010.03408.x PMID: 21118206 Diamond Proposal Number(s): [486] Show Abstract ▼ Abstract: There are many cases where it is desirable to reconstruct at high resolution a small volume from a larger sample. Here we describe the outcomes of a reconstruction trial based on real samples aimed at delineating the practical limits to which a small region of interest can be viewed from a large sample. Our approach has been to artificially truncate the sinograms of whole sample scans to simulate region of interest tomography. A simple filtered back projection algorithm has been applied, with the sinograms extended laterally in a simple manner to make up for the truncated portions. The impact of the degree of truncation (from 0% down to 99%), the number of projections used, as well as the position of the region of interest, on the faithfulness of the reconstruction is evaluated for a range of sample types. We have assessed the nature of, and extent to which, artefacts are introduced and the degree to which simple strategies can minimize them to an acceptable level without the need for complex reconstruction algorithms, projection stitching strategies or very large detectors. It is found that for a wide range of objects the effect of truncation on feature detection is negligible and that excellent images can be reconstructed if the number of projections is calculated not on the basis of the number of pixels on the camera, but on the number of pixels that would be required to scan the whole sample at the chosen pixel resolution. This paper demonstrates that in many cases more sophisticated reconstruction strategies are not necessary.	Jun 2010

Publications Database

Search Results

You searched for all publications:

Search Again...

Subject Areas (check all that apply) select all

Instruments used to collect data (check all that apply) select all

Collaborations involved (check all that apply) select all

Diamond Offline Facilities used

Relevant Technical Areas (check all that apply) select all

Menu for Anonymous User