Redlichia nobilis Walcott, 1905, the oldest trilobite in South Korea: age and morphologic restoration by strain analysis

Significant progress towards a fundamental understanding of transformation toughening in composite zirconia ceramics was made possible by the application of a TEM contrast analysis technique for imaging elastic strains. Spherical zirconia particles dispersed in a large-grained alumina matrix were examined by 1 MeV HVEM to simulate bulk conditions. A thermal contraction mismatch arose on cooling from the processing temperature of 1500°C to RT. Tetragonal ZrO2 contracted amisotropically with α(ct) = 16 X 10-6/°C and α(at) = 11 X 10-6/°C and faster than Al2O3 which contracted relatively isotropically at α = 8 X 10-6/°C. A volume increase of +4.9% accompanied the transformation to monoclinic symmetry at room temperature. The elastic strain field surrounding a particle before transformation was 3-dimensionally correlated with the internal crystallographic orientation of the particle and with the strain field after transformation. The aim of this paper is to theoretically and experimentally describe this technique using the ZrO2 as an example and thereby to illustrate the experimental requirements Tor such an analysis in other systems.

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Strain analysis with nanometer resolution using a conventional transmission electron microsopy technique: electron diffraction contrast imaging revisited

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137215 ◽

1995 ◽

Vol 53 ◽

pp. 168-169

Author(s):

Koenraad G F Janssens ◽

Omer Van der Biest ◽

Jan Vanhellemont ◽

Herman E Maes ◽

Robert Hull

Keyword(s):

Electron Diffraction ◽

Strain Field ◽

Elastic Strain ◽

Strain Analysis ◽

Local Strain ◽

Contrast Imaging ◽

Strain Characterization ◽

Physical Mechanisms ◽

Diffraction Contrast ◽

Transmission Electron

There is a growing need for elastic strain characterization techniques with submicrometer resolution in several engineering technologies. In advanced material science and engineering the quantitative knowledge of elastic strain, e.g. at small particles or fibers in reinforced composite materials, can lead to a better understanding of the underlying physical mechanisms and thus to an optimization of material production processes. In advanced semiconductor processing and technology, the current size of micro-electronic devices requires an increasing effort in the analysis and characterization of localized strain. More than 30 years have passed since electron diffraction contrast imaging (EDCI) was used for the first time to analyse the local strain field in and around small coherent precipitates1. In later stages the same technique was used to identify straight dislocations by simulating the EDCI contrast resulting from the strain field of a dislocation and comparing it with experimental observations. Since then the technique was developed further by a small number of researchers, most of whom programmed their own dedicated algorithms to solve the problem of EDCI image simulation for the particular problem they were studying at the time.

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The Evolution of the South Korea–United States Alliance

10.1017/9781316221792 ◽

2018 ◽

Cited By ~ 2

Author(s):

Uk Heo ◽

Terence Roehrig

Keyword(s):

United States ◽

South Korea ◽

The South

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Modulation of carotid strain by statin therapy in atherosclerosis patients

VASA ◽

10.1024/0301-1526/a000596 ◽

2017 ◽

Vol 46 (2) ◽

pp. 108-115 ◽

Cited By ~ 3

Author(s):

Christian Alexander Schaefer ◽

Anna Katharina Blatzheim ◽

Sebastian Gorgonius Passon ◽

Kristin Solveig Pausewang ◽

Nadjib Schahab ◽

...

Keyword(s):

Statin Therapy ◽

Pulse Wave ◽

Ultrasound Examination ◽

Ankle Brachial Index ◽

Radial Strain ◽

Strain Analysis ◽

Duplex Ultrasound ◽

Strain Imaging ◽

The Common

Abstract. Background: The beneficial effect of statin therapy on the progress of atherosclerotic disease has been demonstrated by numerous studies. Vascular strain imaging is an arising method to evaluate arterial stiffness. Our study examined whether an influence of statin therapy on the vessel wall could be detected by vascular strain imaging. Patients and methods: 88 patients with recently detected atherosclerosis underwent an angiological examination including ankle-brachial index (ABI), pulse wave index (PWI), central puls ewave velocity and duplex ultrasound. Captures for vascular strain analysis were taken in B-mode during ultrasound examination of the common carotid artery and evaluated using a workstation equipped with a speckle tracking based software. A statin therapy was recommended and after six months a follow-up examination took place. Meanwhile, the non-adherence of a group of patients (N = 18) lead to a possibility to observe statin effects on the vascular strain. Results: In the statin non-adherent group the ABI decreased significantly to a still non-pathological level (1.2 ± 0.2 vs. 1.0 ± 0.2; p = 0.016) whereas it stagnated in the adherent group (1.0 ± 0.2 vs. 1.0 ± 0.2; p = 0.383). The PWI did not differ in the non-adherent group (180.5 ± 71.9 vs. 164.4 ± 75.8; p = 0.436) but under statin therapy it decreased significantly (261.8 ± 238.6 vs. 196.4 ± 137.4; p = 0.016). In comparison to the adherent group (4.2 ± 2.0 vs. 4.0 ± 1.8; p = 0.548) under statin therapy the radial strain decreased significantly in the non-adherent group (4.7 ± 2.0 vs. 3.3 ± 1.1; p = 0.014). Conclusions: Our findings reveal a beneficial influence of statin therapy on the arterial wall detected by vascular strain analysis.

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