On the Role of Characterization in the Design of Interfaces in Nanoscale Materials Technology

2004 ◽  
Vol 10 (3) ◽  
pp. 324-335 ◽  
Author(s):  
S.P. Ringer ◽  
K.R. Ratinac

This work reviews recent research on the design and control of interfaces in engineering nanomaterials. Four case studies are presented that demonstrate the power of a multimodal approach to the characterization of different types of interfaces. We have used a combination of conventional, high resolution, and analytical transmission electron microscopy, microbeam electron diffraction, and three-dimensional atom probe to study polymer–clay nanocomposites, turbine rotor steels used for power generation, multicomponent aluminum alloys, and nanocrystalline magnetic materials.

2010 ◽  
Vol 16 (5) ◽  
pp. 636-642 ◽  
Author(s):  
Christopher J. Tourek ◽  
Sriram Sundararajan

AbstractThree-dimensional atom probe tomography (APT) is successfully used to analyze the near-apex regions of an atomic force microscope (AFM) tip. Atom scale material structure and chemistry from APT analysis for standard silicon AFM tips and silicon AFM tips coated with a thin film of Cu is presented. Comparison of the thin film data with that observed using transmission electron microscopy indicates that APT can be reliably used to investigate the material structure and chemistry of the apex of an AFM tip at near atomic scales.


2012 ◽  
Vol 463-464 ◽  
pp. 20-24
Author(s):  
Kai Zhao

More attention has been paid to the interfaces since mechanical properties of nickel-base superalloys are determined to some degree by them. The compositional transition across γ/γ′ interfaces and atomic structure of the interfaces was investigated using three-dimensional atom probe tomography and scanning transmission electron microscope equipped with high-resolution Energy Dispersive X-ray Spectrometry. Results show that no obvious segregation to the interfaces or ledges of the precipitates in the present experimental alloys has been observed. Also, adsorption of a solute to the interface was not observed. The interfaces are not flat as usually thought at an atomic scale. The interfacial thickness is about two atomic layers, i.e. 0.7 nm.


2008 ◽  
Vol 14 (S2) ◽  
pp. 1240-1241
Author(s):  
J Hwang ◽  
R Banerjee ◽  
M Kaufman

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008


Author(s):  
J. A. Eades ◽  
A. E. Smith ◽  
D. F. Lynch

It is quite simple (in the transmission electron microscope) to obtain convergent-beam patterns from the surface of a bulk crystal. The beam is focussed onto the surface at near grazing incidence (figure 1) and if the surface is flat the appropriate pattern is obtained in the diffraction plane (figure 2). Such patterns are potentially valuable for the characterization of surfaces just as normal convergent-beam patterns are valuable for the characterization of crystals.There are, however, several important ways in which reflection diffraction from surfaces differs from the more familiar electron diffraction in transmission.GeometryIn reflection diffraction, because of the surface, it is not possible to describe the specimen as periodic in three dimensions, nor is it possible to associate diffraction with a conventional three-dimensional reciprocal lattice.


Author(s):  
HAIYAN DUAN ◽  
KAMRAN AHMED ◽  
MARTHIN NANERE

We examine the effects of different types of executive incentives on technological innovation of declining firms and the moderating effects of the degree of decline and organisational slack on executive incentives and enterprise technological innovation. We also assess the synergetic effects of different types of executive incentives on technological innovation of declining enterprises. We find the following: first, executive compensation incentive, equity incentive and control incentives are beneficial to promote technological innovation in declining enterprises. Second, the degree of decline negatively moderates the relationship between equity incentive and technological innovation. Third, organisational slack positively moderates the relationship between equity incentive and technological innovation, as well as the relationship between control incentives and technological innovation, especially for severely declining enterprises. Fourth, there are synergistic effects between executive control incentive and compensation incentive, control incentives and equity incentive on technological innovation. The contributions are as follows: first, taking declining enterprises as sample, we suggest that to increase the role of compensation incentive and equity incentive in promoting technological innovation in declining enterprises, the control incentives should be strengthened. Second, organisational slack should be fully exploited for severely declining enterprises so that executives should have the motivation and conditions to carry out technological innovation and further help declining enterprises to turnaround successfully.


Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1397 ◽  
Author(s):  
Elaine dos Santos ◽  
Marcus Fook ◽  
Oscar Malta ◽  
Suédina de Lima Silva ◽  
Itamara Leite

Purified clay was modified with different amounts of alkyl ammonium and phosphonium salts and used as filler in the preparation of PET nanocomposites via melt intercalation. The effect of this type of filler on morphology and thermal and mechanical properties of PET nanocomposites was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile properties, and transmission electron microscopy (TEM). The results showed that the mixture of alkyl ammonium and phosphonium salts favored the production of PET nanocomposites with intercalated and partially exfoliated morphologies with slight improvement in thermal stability. In addition, the incorporation of these organoclays tended to inhibit PET crystallization behavior, which is profitable in the production of transparent bottles.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Licong Peng ◽  
Kosuke Karube ◽  
Yasujiro Taguchi ◽  
Naoto Nagaosa ◽  
Yoshinori Tokura ◽  
...  

AbstractDriving and controlling single-skyrmion motion promises skyrmion-based spintronic applications. Recently progress has been made in moving skyrmionic bubbles in thin-film heterostructures and low-temperature chiral skyrmions in the FeGe helimagnet by electric current. Here, we report the motion tracking and control of a single skyrmion at room temperature in the chiral-lattice magnet Co9Zn9Mn2 using nanosecond current pulses. We have directly observed that the skyrmion Hall motion reverses its direction upon the reversal of skyrmion topological number using Lorentz transmission electron microscopy. Systematic measurements of the single-skyrmion trace as a function of electric current reveal a dynamic transition from the static pinned state to the linear flow motion via a creep event, in agreement with the theoretical prediction. We have clarified the role of skyrmion pinning and evaluated the intrinsic skyrmion Hall angle and the skyrmion velocity in the course of the dynamic transition. Our results pave a way to skyrmion applications in spintronic devices.


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