scholarly journals Three-Dimensional Structural Analysis of Ferromanganese Nodules from the Western North Pacific Ocean Using X-ray Computed Tomography

Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1100
Author(s):  
Kentaro Nakamura ◽  
Daiki Terauchi ◽  
Ryo Shimomura ◽  
Shiki Machida ◽  
Kazutaka Yasukawa ◽  
...  

The three-dimensional layered growth structure of 934 ferromanganese nodule samples collected from dives in the Pacific Ocean around Minamitorishima Island was assessed using X-ray computed tomography (X-ray CT) to elucidate their growth history. The thickness of the layered structure measured in three orthogonal directions showed that the ferromanganese nodules grew equally in all directions regardless of shape and size. Based on differences in CT numbers, a layered structure was subdivided into sublayers I, II, III, and IV, which corresponded to petrological features. The nodules were then classified as Types I, II, III, and IV according to whether they had sublayers I, I and II, I–III, or I–IV, respectively. Correlations between the total thickness of the layers and the number of sublayers indicated that both represented the relative age of the nodules. Nodules with all these types were recovered from most of the sampling sites, and histograms of the total layer thickness at each dive site showed several peaks. These findings indicated that the initiation of nodule growth was intermittent, rather than simultaneous. Three distinct thickness peaks were found at many sites throughout the study area, suggesting that at least three nodule initiation events covering hundreds of kilometers initiated the growth of ferromanganese nodules.

2021 ◽  
Author(s):  
Katherine A. Wolcott ◽  
Guillaume Chomicki ◽  
Yannick M. Staedler ◽  
Krystyna Wasylikowa ◽  
Mark Nesbitt ◽  
...  

Author(s):  
Theodore J. Heindel ◽  
Terrence C. Jensen ◽  
Joseph N. Gray

There are several methods available to visualize fluid flows when one has optical access. However, when optical access is limited to near the boundaries or not available at all, alternative visualization methods are required. This paper will describe flow visualization using an X-ray system that is capable of digital X-ray radiography, digital X-ray stereography, and digital X-ray computed tomography (CT). The unique X-ray flow visualization facility will be briefly described, and then flow visualization of various systems will be shown. Radiographs provide a two-dimensional density map of a three dimensional process or object. Radiographic images of various multiphase flows will be presented. When two X-ray sources and detectors simultaneously acquire images of the same process or object from different orientations, stereographic imaging can be completed; this type of imaging will be demonstrated by trickling water through packed columns and by absorbing water in a porous medium. Finally, local time-averaged phase distributions can be determined from X-ray computed tomography (CT) imaging, and this will be shown by comparing CT images from two different gas-liquid sparged columns.


2003 ◽  
Vol 8 (1) ◽  
pp. 2-6 ◽  
Author(s):  
Wolfgang H Stuppy ◽  
Jessica A Maisano ◽  
Matthew W Colbert ◽  
Paula J Rudall ◽  
Timothy B Rowe

2018 ◽  
Vol 139 ◽  
pp. 75-82 ◽  
Author(s):  
A.H. Galmed ◽  
A. du Plessis ◽  
S.G. le Roux ◽  
E. Hartnick ◽  
H. Von Bergmann ◽  
...  

Author(s):  
P Potamianos ◽  
A A Amis ◽  
A J Forester ◽  
M McGurk ◽  
M Bircher

The revision of an orthopaedic procedure can present surgeons with the challenge of a complex reconstructive process. Orthopaedic surgery can also face considerable challenges in cases presenting extensive primary injuries with multiple bone fragmentation, as well as in cases presenting bone deformities. Radiographs are used routinely for orthopaedic surgical planning, yet they provide inadequate information on the precise three-dimensional extent of bone defects. Three-dimensional reconstructions from X-ray computed tomography offer superior visualization but are not portable for consultation or readily available in the operating theatre for guidance during a procedure. A physical model manufactured from X-ray computed tomography data can offer surgeons a clear understanding of complex anatomical detail, by providing an intuitive physical relationship between patient and model. Rapid prototyping was used for the construction of an anatomical model in a case presenting with a complex shoulder injury. The model provided a definitive interpretation of joint pathology and enabled a full assessment of the degree of injury.


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