Kossel technique by means of synchrotron beam excitation - a new method for material characterization

This work presents five different methods for quantifying the segregation phenomenon in lightweight aggregate concretes (LWAC). The use of LWACs allows greater design flexibility and substantial cost savings, and has a positive impact on the energy consumption of a building. However, these materials are susceptible to aggregate segregation, which causes an irregular distribution of the lightweight aggregates in the mixture and may affect the concrete properties. To quantify this critical process, a new method based on image analysis is proposed and its results are compared to the well-established methods of density and ultrasonic pulse velocity measurement. The results show that the ultrasonic test method presents a lower accuracy than the other studied methods, although it is a nondestructive test, easy to perform, and does not need material characterization. The new methodology via image analysis has a strong correlation with the other methods, it considers information from the complete section of the samples, and it does not need the horizontal cut of the specimens or material characterization.

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Electrical response during indentation of piezoelectric materials: A new method for material characterization

Journal of Applied Physics ◽

10.1063/1.369459 ◽

1999 ◽

Vol 85 (1) ◽

pp. 380-387 ◽

Cited By ~ 50

Author(s):

S. Sridhar ◽

A. E. Giannakopoulos ◽

S. Suresh ◽

U. Ramamurty

Keyword(s):

Material Characterization ◽

Piezoelectric Materials ◽

Electrical Response ◽

New Method

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Crystallographic Texture Analysis as a New Method for Material Characterization

Nondestructive Characterization of Materials IV ◽

10.1007/978-1-4899-0670-0_52 ◽

1991 ◽

pp. 429-438 ◽

Cited By ~ 1

Author(s):

J. R. Hirsch

Keyword(s):

Texture Analysis ◽

Crystallographic Texture ◽

Material Characterization ◽

New Method

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Resolution, Contrast and Interpretation of HVEM Images of Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071582 ◽

1973 ◽

Vol 31 ◽

pp. 228-229

Author(s):

L. E. Thomas ◽

J. S. Lally ◽

R. M. Fisher

Keyword(s):

High Voltage ◽

Chromatic Aberration ◽

Crystalline Materials ◽

Resolution Parameter ◽

Instrument Resolution ◽

Imaging Conditions ◽

Beam Excitation ◽

Optimum Imaging

In addition to improved penetration at high voltage, the characteristics of HVEM images of crystalline materials are changed markedly as a result of many-beam excitation effects. This leads to changes in optimum imaging conditions for dislocations, planar faults, precipitates and other features.Resolution - Because of longer focal lengths and correspondingly larger aberrations, the usual instrument resolution parameter, CS174 λ 374 changes by only a factor of 2 from 100 kV to 1 MV. Since 90% of this change occurs below 500 kV any improvement in “classical” resolution in the MVEM is insignificant. However, as is widely recognized, an improvement in resolution for “thick” specimens (i.e. more than 1000 Å) due to reduced chromatic aberration is very large.

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Selective Sampling and Orientation of Non-Homogeneous Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100238 ◽

1968 ◽

Vol 26 ◽

pp. 98-99

Author(s):

C. C. Clawson ◽

L. W. Anderson ◽

R. A. Good

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Light Microscopy ◽

Random Sampling ◽

New Method ◽

Microscope Examination ◽

Small Areas ◽

Selective Sampling ◽

Large Numbers ◽

Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

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