In-Situ Geotechnical Characterization of Mixed-Grain-Size Bedforms Using A Dynamic Penetrometer

2012 ◽  
Vol 82 (7) ◽  
pp. 540-544 ◽  
Author(s):  
N. Stark ◽  
G. Coco ◽  
K. R. Bryan ◽  
A. Kopf
Keyword(s):  
Grain Size ◽  
Geotechnical Characterization

In situ geotechnical characterization of sediments on the Nova Scotian Slope, eastern Canadian continental margin

1994 ◽  
Vol 120 (3-4) ◽  
pp. 291-308 ◽  
Author(s):  
Agnes Baltzer ◽  
Pierre Cochonat ◽  
David J.W Piper
Keyword(s):  
Continental Margin ◽  
Geotechnical Characterization ◽  
Nova Scotian

Synthesis and Characterization of In Situ AlN Reinforced Magnesium Matrix Composites

2012 ◽  
Vol 710 ◽  
pp. 377-382
Author(s):  
Sreeja Kumari Sukumaran Suseelammaa ◽  
Uma Thanu Subramonia Pillai ◽  
Sujayakumar Prasanth ◽  
Bellampettu Chandrasekhar Pai
Keyword(s):  
Grain Size ◽  
Xrd Analysis ◽  
Synthesis And Characterization ◽  
Matrix Composites ◽  
Nitrogen Gas ◽  
Magnesium Matrix ◽  
Magnesium Matrix Composites ◽  
Gas Bubbling

In situ Mg-AlN composite has been synthesized by nitrogen gas bubbling method. The morphology of the particles is found to be hexagonal by SEM. The size of the AlN particles is found to be in the range from nano, submicron to a few microns. XRD analysis of the samples confirms the formation of AlN in the melt. Further, the grain size of the magnesium matrix has been reduced by the presence of AlN particles. Hardness of the composite is significantly increased in the particle rich area due to the presence of hard AlN particles.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

A very rapid in situ Kikuchi technique to determine relative crystal misorientation

1988 ◽  
Vol 46 ◽  
pp. 830-831
Author(s):  
J. I. Bennetch
Keyword(s):  
Electron Beam ◽  
Analytical Techniques ◽  
Superplastic Forming ◽  
The Other ◽  
Kikuchi Pattern ◽  
Kikuchi Line ◽  
Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

Coherent electron nanodiffraction from clean silver nano particles in a UHV STEM

1993 ◽  
Vol 51 ◽  
pp. 1058-1059
Author(s):  
J. Liu ◽  
M. Pan ◽  
G. E. Spinnler
Keyword(s):  
Supported Catalysts ◽  
Imaging Techniques ◽  
Nano Particles ◽  
Metal Particles ◽  
Shape Structure ◽  
Dynamical Simulations ◽  
Small Metal Particles ◽  
Extract Information

Small metal particles have peculiar chemical and physical properties as compared to bulk materials. They are especially important in catalysis since metal particles are common constituents of supported catalysts. The structural characterization of small particles is of primary importance for the understanding of structure-catalytic activity relationships. The shape and size of metal particles larger than approximately 5 nm in diameter can be determined by several imaging techniques. It is difficult, however, to deduce the shape of smaller metal particles. Coherent electron nanodiffraction (CEND) patterns from nano particles contain information about the particle size, shape, structure and defects etc. As part of an on-going program of STEM characterization of supported catalysts we report some preliminary results of CEND study of Ag nano particles, deposited in situ in a UHV STEM instrument, and compare the experimental results with full dynamical simulations in order to extract information about the shape of Ag nano particles.

Characterization of the glycoconjugates of boar testis and epididymis

Reproduction ◽  
2000 ◽  
pp. 325-335 ◽  
Author(s):  
A Calvo ◽  
LM Pastor ◽  
S Bonet ◽  
E Pinart ◽  
M Ventura
Keyword(s):  
Ricinus Communis ◽  
Lectin Histochemistry ◽  
Apical Part ◽  
Seminiferous Tubules ◽  
In Situ Characterization ◽  
Intense Staining ◽  
Terminal Galactose ◽  
Boar Spermatozoa

Lectin histochemistry was used to perform in situ characterization of the glycoconjugates present in boar testis and epididymis. Thirteen horseradish peroxidase- or digoxigenin-labelled lectins were used in samples obtained from healthy fertile boars. The acrosomes of the spermatids were stained intensely by lectins with affinity for galactose and N-acetyl-galactosamine residues, these being soybean, peanut and Ricinus communis agglutinins. Sertoli cells were stained selectively by Maackia ammurensis agglutinin. The lamina propria of seminiferous tubules showed the most intense staining with fucose-binding lectins. The Golgi area and the apical part of the principal cells of the epididymis were stained intensely with many lectins and their distribution was similar in the three zones of the epididymis. On the basis of lectin affinity, both testis and epididymis appear to have N- and O-linked glycoconjugates. Spermatozoa from different epididymal regions showed different expression of terminal galactose and N-acetyl-galactosamine. Sialic acid (specifically alpha2,3 neuraminic-5 acid) was probably incorporated into spermatozoa along the extratesticular ducts. These findings indicate that the development and maturation of boar spermatozoa are accompanied by changes in glycoconjugates. As some lectins stain cellular or extracellular compartments specifically, these lectins could be useful markers in histopathological evaluation of diseases of boar testis and epididymis.

Structural and Electrical Characterization of Shaped Beam Laser Recrystallized Polysilicon on Amorphous Substrates

1981 ◽  
Vol 4 ◽  
Author(s):  
T. J. Stultz ◽  
J. F. Gibbons
Keyword(s):  
Grain Size ◽  
Electrical Characterization ◽  
Grain Structure ◽  
Electrical Characteristics ◽  
Shaped Beam ◽  
Beam Laser ◽  
Cw Laser ◽  
Amorphous Substrates ◽  
Circular Beam

ABSTRACTStructural and electrical characterization of laser recrystallized LPCVD silicon films on amorphous substrates using a shaped cw laser beam have been performed. In comparing the results to data obtained using a circular beam, it was found that a significant increase in grain size can be achieved and that the surface morphology of the shaped beam recrystallized material was much smoother. It was also found that whereas circular beam recrystallized material has a random grain structure, shaped beam material is highly oriented with a <100> texture. Finally the electrical characteristics of the recrystallized film were very good when measured in directions parallel to the grain boundaries.

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