Structure stabilization effect of configuration entropy in cubic WN

Layered stacking characteristics of ternary Zr–Al–C carbides were investigated using scanning transmission electron microscopy (STEM). Three previously unknown compounds, i.e., Zr4Al3C6, Zr5Al6C9, and Zr7Al6C11 were identified. The present study extends the structural information of ternary Zr–Al–C ceramics. The influence of the thickness of the NaCl-type Zr-C slab on the elastic properties of ternary Zr–Al–C ceramics is discussed based on first-principles calculations. In addition, direct atomic-resolution observations illustrate the process for forming the unique layered crystal structures of ternary Zr–Al–C ceramics. These results also provide insights into the formation mechanism of layered ternary Zr–Al–C carbides.

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Coupling Atom Probe Tomography with Aberration-Corrected Scanning Transmission Electron Microscopy and First-Principles Computations to Investigate Omega Precipitation in Titanium Alloys

Microscopy and Microanalysis ◽

10.1017/s1431927613006727 ◽

2013 ◽

Vol 19 (S2) ◽

pp. 946-947

Author(s):

S. Nag ◽

A. Devaraj ◽

N. Gupta ◽

R. Williams ◽

S. Srivilliputhur ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Titanium Alloys ◽

First Principles ◽

Atom Probe Tomography ◽

Scanning Transmission Electron Microscopy ◽

Atom Probe ◽

Transmission Electron ◽

Scanning Transmission ◽

Aberration Corrected

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

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High-Voltage Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067029 ◽

1970 ◽

Vol 28 ◽

pp. 6-7

Author(s):

J. M. Cowley

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Wave Optics ◽

Contrast Effects ◽

Transmission Electron ◽

Mode Of Operation ◽

Scanning Transmission ◽

Types Of Information ◽

Voltage Scanning

The comparison of scanning transmission electron microscopy (STEM) with conventional transmission electron microscopy (CTEM) can best be made by means of the Reciprocity Theorem of wave optics. In Fig. 1 the intensity measured at a point A’ in the CTEM image due to emission from a point B’ in the electron source is equated to the intensity at a point of the detector, B, due to emission from a point A In the source In the STEM. On this basis it can be demonstrated that contrast effects In the two types of instrument will be similar. The reciprocity relationship can be carried further to include the Instrument design and experimental procedures required to obtain particular types of information. For any. mode of operation providing particular information with one type of microscope, the analagous type of operation giving the same information can be postulated for the other type of microscope. Then the choice between the two types of instrument depends on the practical convenience for obtaining the required Information.

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Scanning Transmission Electron Microscopy of Polyethylene Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001069 ◽

1980 ◽

Vol 38 ◽

pp. 242-245

Author(s):

F. Khoury ◽

L. H. Bolz

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallization Temperature ◽

Scanning Transmission Electron Microscopy ◽

Growth Habit ◽

Lateral Growth ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Growth Habits

The lateral growth habits and non-planar conformations of polyethylene crystals grown from dilute solutions (<0.1% wt./vol.) are known to vary depending on the crystallization temperature.1-3 With the notable exception of a study by Keith2, most previous studies have been limited to crystals grown at <95°C. The trend in the change of the lateral growth habit of the crystals with increasing crystallization temperature (other factors remaining equal, i.e. polymer mol. wt. and concentration, solvent) is illustrated in Fig.l. The lateral growth faces in the lozenge shaped type of crystal (Fig.la) which is formed at lower temperatures are {110}. Crystals formed at higher temperatures exhibit 'truncated' profiles (Figs. lb,c) and are bound laterally by (110) and (200} growth faces. In addition, the shape of the latter crystals is all the more truncated (Fig.lc), and hence all the more elongated parallel to the b-axis, the higher the crystallization temperature.

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