Characterization of Surface Roughness in Thin Films and Small Particles

ABSTRACTThe surface roughness of small metallic particles and thin films is determined using TEM weak beam dark field images (WBDF) combined with image processing techniques. It is shown that the well known sensitivity of WBDF images to monoatomic steps on the sample surface can be largely improved by the use of image processing. The optimum conditions for step imaging and for the processing for small particles of Au, Pt and Pd and thin films of Au and Ag are discussed. It is found that under most conditions the surface of the particles and the films is very rough at the atomic level in agreement with the current theories of crystal growth.

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Planar Defects in Small Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118837 ◽

1985 ◽

Vol 43 ◽

pp. 392-393

Author(s):

R. Pérez ◽

M. Avalos-Borja

Keyword(s):

Stacking Faults ◽

Particle Growth ◽

Small Particles ◽

Planar Defects ◽

Metallic Particles ◽

Weak Beam ◽

Transmission Electron ◽

Imaging Conditions

Transmission electron microscope techniques have been extensively used in the determination of the morphology of fine metallic particles. These techniques have been of particular importance in obtaining topographical information during particle growth and sintering. Thus, for example, it has been found that some of the most elementary forms consist of half cubo-octahedral units with (111) faces and (100) basis. Furthermore, full cubo-octahedral units have also been found, some of them showing stacking faults (SF) through the particles.It is important to point out that the characterization of this type of planar defects in small metallic particles has commonly been based on geometrical con. siderations. Additionally, the imaging conditions which have been used are the so-called weak beam (WB) diffraction conditions. Recent investigations have shown, on the other hand, that SF images under WB conditions present serious inconveniences, for example, contrast asymmetries in SF images which are not totally explained. Another difficulty with these WB fault images arises from twin boundaries which display image contrast similar to SF when a common reflection is strongly excited.

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Direct Evidence of Surface Roughness in Small Metallic Particles

MRS Proceedings ◽

10.1557/proc-368-133 ◽

1994 ◽

Vol 368 ◽

Author(s):

Miguel Jose Yacaman ◽

Samuel Tehuacanero ◽

Cristina Zorrilla ◽

Gabriela Diaz

Keyword(s):

Electron Microscopy ◽

Image Processing ◽

Surface Roughness ◽

Direct Evidence ◽

High Resolution Electron Microscopy ◽

Detailed Structure ◽

Metallic Particles ◽

New Information ◽

Resolution Electron

ABSTRACTThe characterization of nanoparticles is of prime importance in catalysis. High Resolution Electron Microscopy coupled with image processing has produce a lot of new information on the detailed structure of the particles. In this paper we discuss the possibility of applying these techniques to the study of surface roughness.

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Applications of image processing techniques to the structural characterization of small metallic particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106259 ◽

1988 ◽

Vol 46 ◽

pp. 838-839

Author(s):

R. Pérez ◽

J.G. Pérez-Ramírez

Keyword(s):

Image Processing ◽

Structural Characteristics ◽

Fold Axis ◽

Gold Particles ◽

Metallic Particles ◽

Image Processing Techniques ◽

Transmission Electron ◽

Lattice Resolution ◽

Processing Techniques

Digital image processing techniques have become one of the main tools on image characterization in transmission electron microscopy. Applications of these techniques in the field of small metallic particles are widely known. The results presented in this communication explore some of the structural characteristics of decahedral gold particles. The work is based on HREM images of these type of particles obtained along five-fold axis.Small gold particles have been prepared by evaporation onto a vacuum cleaved NaCl surface. Lattice resolution images and microdiffraction patterns from individual particles have been obtained. Some of the images have been digitized with a scanning microdensitometer and computer processed.Fig. 1 shows a HREM image of a decahedral gold particle obtained under diffraction conditions close to a five-fold zone axis. This image has been digitized and a computed “microdiffraction” pattern has been obtained from each of the five segments.

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IVUS Image Processing Methodologies

Image Processing ◽

10.4018/978-1-4666-3994-2.ch033 ◽

2013 ◽

pp. 639-657

Author(s):

Antonis A. Sakellarios ◽

Christos V. Bourantas ◽

Lambros S. Athanasiou ◽

Dimitrios I. Fotiadis ◽

Lampros K. Michalis

Keyword(s):

Image Processing ◽

Vessel Wall ◽

Regions Of Interest ◽

Manual Segmentation ◽

Arterial Lumen ◽

Ivus Image ◽

Processing Techniques ◽

Automated Methods

Intravascular Ultrasound (IVUS) is an invasive imaging technique that allows detailed visualization of the arterial lumen and outer vessel wall and permits characterization of the type of the plaque and quantification of its burden. Traditionally IVUS processing was performed manually. However, it became apparent that manual segmentation is time consuming, and the obtained results depend on the experience of the operators. To overcome these limitations and enhance the role of IVUS in clinical practice and research, several (semi-) automated methods have been developed that expedite detection of the regions of interest and/or characterization of the type of the plaque. In this chapter we review the available IVUS processing techniques and present the developed commercial solutions for IVUS segmentation and plaque characterization.

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Morphological and Chemical Characterization of Titanium and Zirconia Dental Implants with Different Macro- and Micro-Structure

Applied Sciences ◽

10.3390/app10217520 ◽

2020 ◽

Vol 10 (21) ◽

pp. 7520

Author(s):

Maria Menini ◽

Francesco Pera ◽

Francesco Bagnasco ◽

Francesca Delucchi ◽

Elisa Morganti ◽

...

Keyword(s):

Surface Roughness ◽

Dental Implants ◽

Chemical Characterization ◽

Sample Surface ◽

Titanium Implants ◽

Good Care ◽

Micro Structure ◽

Chemical Residues ◽

Micro Structures

Background: The aim of this study was to evaluate the macro- and micro-structure and the chemical composition of the surface of 5 different commercially available dental implants. Roughness values were also calculated. Materials and Methods: 1 zirconia implant (NobelPearl of Nobel Biocare) and 4 titanium implants, Syra (Sweden&Martina), Prama (Sweden&Martina), T3 (Biomet 3i), and Shard (Mech&Human), were analyzed through SEM-EDX analysis and quantitative evaluation of surface roughness (1 sample), and XPS chemical analysis (1 sample). Surface roughness was quantitatively assessed using the stereo-SEM method (SSEM). The following area roughness parameters were calculated, according to ISO25178: Sa, Sz, and Sdr. Results: From the SEM observations, all the implants analyzed presented modern well-developed micro-structures as the result of the specific process of double acid etching alone or combined with other additional treatments. Roughness values were generally greater at the level of the implant body and lower at the collar. The chemical characterization of the implant surfaces exhibited excellent results for all of the implants and indicated good care in the production processes. Conclusions: All the samples were well-conceived in terms of topography and surface roughness, and clean in terms of chemical residues.

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Characterization of coal porosity and permeability evolution by demineralisation using image processing techniques: A micro-computed tomography study

Journal of Natural Gas Science and Engineering ◽

10.1016/j.jngse.2018.06.020 ◽

2018 ◽

Vol 56 ◽

pp. 384-396 ◽

Cited By ~ 15

Author(s):

Guanglei Zhang ◽

P.G. Ranjith ◽

M.S.A. Perera ◽

Asadul Haque ◽

Xavier Choi ◽

...

Keyword(s):

Computed Tomography ◽

Image Processing ◽

Permeability Evolution ◽

Micro Computed Tomography ◽

Image Processing Techniques ◽

Porosity And Permeability ◽

Processing Techniques

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Ultra-thin films for plasmonics: a technology overview

Nanotechnology Reviews ◽

10.1515/ntrev-2015-0021 ◽

2015 ◽

Vol 4 (3) ◽

Cited By ~ 28

Author(s):

Radu Malureanu ◽

Andrei Lavrinenko

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Support Surface ◽

New Materials ◽

Infra Red ◽

Plasmon Polaritons ◽

Plasmon Propagation ◽

Made In

AbstractUltra-thin films with low surface roughness that support surface plasmon-polaritons in the infra-red and visible ranges are needed in order to improve the performance of devices based on the manipulation of plasmon propagation. Increasing amount of efforts is made in order not only to improve the quality of the deposited layers but also to diminish their thickness and to find new materials that could be used in this field. In this review, we consider various thin films used in the field of plasmonics and metamaterials in the visible and IR range. We focus our presentation on technological issues of their deposition and reported characterization of film plasmonic performance.

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Characterization of Air-Entrainment in a Plunging Water Jet System Using Image Processing: An Educational Approach

Volume 5: Engineering Education and Professional Development ◽

10.1115/imece2011-62371 ◽

2011 ◽

Author(s):

Arman Molki ◽

Lyes Khezzar ◽

Afshin Goharzadeh

Keyword(s):

Image Processing ◽

Free Surface ◽

Flow Behavior ◽

Air Entrainment ◽

Experimental Setup ◽

Water Mixture ◽

Educational Approach ◽

Image Processing Techniques ◽

Processing Techniques

This paper outlines a proposed experimental setup and image processing techniques using MATLAB for the characterization of the average dynamic behavior of the air/water mixture under the free surface of water penetrated by a plunging jet. The proposed setup focuses on the dynamics of air entrainment below the free surface and the identification of the major regimes related to the entrainment process of bubbles in water, namely: (a) no-entrainment, (b) incipient entrainment, (c) intermittent entrainment, and (d) continuous entrainment. The experimental setup allows students to observe the flow behavior below the free liquid surface and determine the penetration depth of the bubble plumes using image processing techniques in MATLAB. The focal point of the experiment is image analysis for qualitative and quantitative characterization of the bubble plume.

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