Lessons learned in the execution of advanced x-ray material discrimination (Conference Presentation)

Author(s):  
Sharene Young
2022 ◽  
pp. 004947552110433
Author(s):  
James Shelton ◽  
Sara Dorman ◽  
Yinna Kim ◽  
Phillipa Thorpe ◽  
Badri Narayan ◽  
...  

Circular frames are a successful way of treating difficult fractures and non-unions. At our institution (CSC) in Phnom Penh, Cambodia, our method differs from developed healthcare systems in that we do not use x-ray to site the frames. A retrospective cohort study was performed between CSC and a UK LRS unit. Demographics, diagnosis, frame type, pre- and post-op deformity, proximal and distal construct alignment comparative to the tibia, and time to union or failure. 70 patients in total were identified and were randomly selected from a hospital in UK. Demographics & deformity were similar and failed to reach significant difference on testing: union rate 70% v. 82%, time to union 9.8 v. 8.5 months, and radiation exposure mean 0 v. 74 cGy/cm2 (range 6.4–326.7). These are startlingly homogenous results considering the differing resources available. We believe that ring fixators are a viable treatment method in austere environments where image intensifiers are unavailable, and demand no unnecessary radiation exposure.


2014 ◽  
Vol 29 (S1) ◽  
pp. S2-S7
Author(s):  
Pamela S. Whitfield

In many ways, studies of materials and minerals by powder-diffraction techniques are complementary, with techniques honed in one field equally applicable to the other. Many of the example techniques described within this paper were developed for analysis of functional materials and subsequently applied to minerals. However, in a couple of cases, the study of new minerals was the initiation into techniques later used in materials-based studies. Hopefully they will show that the study of new minerals structures can provide opportunities to add new methodologies and approaches to future problems. In keeping with the Australian X-ray Analytical Association many of the examples have an Australian connection, the materials ranging from organics to battery materials.


2011 ◽  
Vol 56 (18) ◽  
pp. 5969-5983 ◽  
Author(s):  
S J Nik ◽  
J Meyer ◽  
R Watts

2016 ◽  
Vol 114 ◽  
pp. 188-195 ◽  
Author(s):  
Liang Li ◽  
Ruizhe Li ◽  
Siyuan Zhang ◽  
Tiao Zhao ◽  
Zhiqiang Chen

Author(s):  
Navid Asadizanjani ◽  
Sina Shahbazmohamadi ◽  
Mark Tehranipoor ◽  
Domenic Forte

Abstract Reverse engineering of electronics systems is performed for various reasons ranging from honest ones such as failure analysis, fault isolation, trustworthiness verification, obsolescence management, etc. to dishonest ones such as cloning, counterfeiting, identification of vulnerabilities, development of attacks, etc. Regardless of the goal, it is imperative that the research community understands the requirements, complexities, and limitations of reverse engineering. Until recently, the reverse engineering was considered as destructive, time consuming, and prohibitively expensive, thereby restricting its application to a few remote cases. However, the advents of advanced characterization and imaging tools and software have counteracted this point of view. In this paper, we show how X-ray micro-tomography imaging can be combined with advanced 3D image processing and analysis to facilitate the automation of reverse engineering, and thereby lowering the associated time and cost. In this paper, we demonstrate our proposed process on two different printed circuit boards (PCBs). The first PCB is a four-layer custom designed board while the latter is a more complex commercial system. Lessons learned from this effort can be used to both develop advanced countermeasures and establish a more efficient workflow for instances where reverse engineering is deemed necessary. Keywords: Printed circuit boards, non-destructive imaging, X-ray tomography, reverse engineering.


Minerals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1244
Author(s):  
Natsumi Noda ◽  
Shohei Yamashita ◽  
Yoshio Takahashi ◽  
Megumi Matsumoto ◽  
Yuma Enokido ◽  
...  

Ferrous saponite is a secondary mineral that can be used to reveal the redox state of past aqueous environments on Mars. In mineralogical analyses for ferrous saponite formed in laboratory simulations or contained in future returned samples from Mars, its oxidation by the Earth’s air could be problematic due to the high redox sensitivity. Here, we performed micro X-ray diffraction and scanning transmission X-ray microscopy analyses for a single particle of synthesized ferrous saponite without any exposure to air. The sample was reanalyzed after air exposure for 10–18 h to assess the adequacy of our anoxic preparation/measurement methods and the impacts of air on the sample. We found that the crystal structures agreed with ferrous saponite, both before and after air exposure; however, ferrous iron in saponite was partially oxidized, at least until 0.1–1 μm from the surface, after air exposure at the submicron scale, forming micro-vein-like Fe(III)-rich features. Together with our results of infrared spectroscopy of ferrous saponite, we showed that oxidation of octahedral iron occurred rapidly and heterogeneously, even in a short time of air exposure without any structural rearrangement. Since ferrous saponite is expected to exist on carbonaceous asteroids and icy dwarf planets, our methodology is also applicable to mineralogical studies of samples returned from these bodies.


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