Dynamic Behaviour of Lead Nanoparticles in A Dielectric Matrix

1994 ◽  
Vol 332 ◽  
Author(s):  
P. Cheyssac ◽  
R. Kofman ◽  
P. G. Merli ◽  
A. Migliori ◽  
A. Stella
Keyword(s):  
Electron Microscopy ◽  
Liquid Phase ◽  
High Resolution ◽  
Dynamic Behaviour ◽  
Dark Field ◽  
Solid Particles ◽  
Phase Fluctuations ◽  
Dielectric Matrix ◽  
Size Dependent ◽  
Solid Liquid

ABSTRACTIn this paper we present electron microscopy results near and below the melting temperature, both in dark field and high resolution mode, of lead nanoparticles embedded in a dielectric matrix of amorphous SiOx. Three different size dependent regimes are distinguished. Indications of solid particles rotations as well as of a new phenomenon amenable to spontaneous solid-liquid phase fluctuations will be briefly discussed.

A Preparation of High Resolution Standards for Electron Microscopy. Part II

1971 ◽  
Vol 29 ◽  
pp. 160-161
Author(s):  
Akira Tanaka ◽  
David F. Harling
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Single Crystal ◽  
Dark Field ◽  
Graphitized Carbon Black ◽  
Graphitized Carbon ◽  
Dark Field Imaging ◽  
Crystal Films ◽  
Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

scholarly journals Analytical High-resolution Electron Microscopy Reveals Organ-specific Nanoceria Bioprocessing

2017 ◽  
Vol 46 (1) ◽  
pp. 47-61 ◽  
Author(s):  
Uschi M. Graham ◽  
Robert A. Yokel ◽  
Alan K. Dozier ◽  
Lawrence Drummy ◽  
Krishnamurthy Mahalingam ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Analytical Electron Microscopy ◽  
High Resolution Electron Microscopy ◽  
Dark Field ◽  
Transmission Electron ◽  
Analytical Electron ◽  
Organ Specific

This is the first utilization of advanced analytical electron microscopy methods, including high-resolution transmission electron microscopy, high-angle annular dark field scanning transmission electron microscopy, electron energy loss spectroscopy, and energy-dispersive X-ray spectroscopy mapping to characterize the organ-specific bioprocessing of a relatively inert nanomaterial (nanoceria). Liver and spleen samples from rats given a single intravenous infusion of nanoceria were obtained after prolonged (90 days) in vivo exposure. These advanced analytical electron microscopy methods were applied to elucidate the organ-specific cellular and subcellular fate of nanoceria after its uptake. Nanoceria is bioprocessed differently in the spleen than in the liver.

Characterization of Pd/V Multilayer Structures by High-Angle Annular Dark-Field Microscopy and High Resolution Tem

1991 ◽  
Vol 238 ◽  
Author(s):  
J. Liu ◽  
Y. Cheng ◽  
G. D. Lewen ◽  
M. B. Stearns
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
High Resolution Electron Microscopy ◽  
Dark Field ◽  
Compositional Variation ◽  
High Angle ◽  
Dark Field Microscopy ◽  
Annular Dark Field ◽  
Chemical Modulation ◽  
Substrate Temperatures

ABSTRACTThe structures of e-beam evaporated Pd/V multilayer thin films, which were fabricated at different substrate temperatures, have been characterized by high-angle annular dark-field microscopy and high resolution electron microscopy techniques. X-ray scattering and crosssectional electron microscopy showed that both the Pd and V layers are composed of small textured crystallites with dominant orientations of Pd (111) and V (110). It is found that Pd/V multilayers with high chemical modulation can be fabricated at substrate temperatures around 350 K and at a deposition rate of 0.2 nm/s. Here high-angle annular dark-field microscopy has been shown to provide direct information about the compositional variation of the interlayers of these ML.

TEM Studies of Ordering in MOCVD-Grown (GaIn)P on GaAs

1987 ◽  
Vol 104 ◽  
Author(s):  
S. McKernan ◽  
B. C. De Cooman ◽  
C. B. Carter ◽  
D. P. Bour ◽  
J. R. Shealy
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Dark Field ◽  
Growth Surface ◽  
Gaas Substrates ◽  
High Resolution Images

ABSTRACTGaxIn(1−x)P epilayers grown on GaAs substrates by MOVPE, for different growth temperatures and values of x∼0.5, have been studied by electron microscopy. The results indicate that under certain conditions the ternary epilayer is ordered parallel to the (111) plane. Dark-field images obtained using the superlattice reflections reveal ordered domains of different orientations. High-resolution images have been obtained from the ordered domains. The structure of these domains is not perfect but contains many planar faults parallel to the growth surface.

High Resolution TEM Studies On Palladium, Rhodium Nanoparticles

2001 ◽  
Vol 7 (S2) ◽  
pp. 1100-1101
Author(s):  
M. José-Yacamán ◽  
M. Marín-Almazo ◽  
J.A. Ascencio
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Indirect Evidence ◽  
High Resolution Electron Microscopy ◽  
Dark Field ◽  
Rhodium Nanoparticles ◽  
Resolution Electron ◽  
Annular Dark Field ◽  
High Resolution Tem ◽  
Important Field

The field of catalysis is one of the most important areas of the nano-sciences for many years. in deed the goal of having a catalyst, with the maximum active area exposed to a chemical reaction, has produced enormous amount of research in nanoparticles. Particularly, the metal nanoparticles study is a very important field in catalysis. Electron Microscopy is one of the techniques that have played a mayor role on studding nanoparticles. Since bright field images, dark field techniques, to the high-resolution atomic images of nanoparticles and more recently the High Angle Annular dark field images or Z-contrast. However this technique provides only indirect evidence of the atomic arrangements on the particles. High Resolution Electron Microscopy (HREM) still appears as a very powerful technique to study nanoparticles and their internal structure. Among the most interesting metals to study is the palladium, which acts for instance as excellent catalyst for hydrogenation of unsaturated hydrocarbons and has many other applications such as environmental catalysts.

Unstained Biological Specimens in High Resolution Electron Microscopy

1974 ◽  
Vol 32 ◽  
pp. 234-235
Author(s):  
M. K. Lamvik ◽  
J. M. Pullman ◽  
A. V. Crewe
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Heavy Atom ◽  
High Resolution Electron Microscopy ◽  
Scanning Transmission Electron Microscope ◽  
Dark Field ◽  
Structural Studies ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Scanning Transmission

Negative staining and high resolution shadowing have been extensively used for structural studies in electron microscopy. However, these techniques cover the specimen with a layer of heavy salt or metal, and hence do not allow determination of true mass distribution or localization of specific sites using heavy atom markers. A prerequisite for such structural studies is an examination of unstained specimens. For thin specimens dark field microscopy must be used to obtain adequate contrast. The scanning transmission electron microscope is preferred for such studies since elastic, energyloss, and unscattered electrons can be recorded and analyzed quantitatively to form images with a minimum of beam-induced damage.

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