Model of object non-destructive technology of road surfaces compaction control

The safety of the earth structures is highly dependent upon the fill compaction quality. Recently developed nondestructive testing techniques (NDT) present many advantages in comparison with conventional field density measurements. Therefore, use of NDT in monitoring of the fill quality appears to be attractive for future pavement geotechnics applications. This paper presents an alternative technology using non-destructive Clegg impact tester for compaction control in silty sand. 132 compaction tests and impact tests with varying values of compaction effort, moisture content, and density were conducted in laboratory. Each observed impact value (Iv) was then considered as a function of its corresponding compaction effort, moisture content and dry density. Results of the study show that for the silty sand tested, the variations of Iv with moisture content are similar to the corresponding unique moisture-density compaction relationship. The values of Iv generally correlate well with moisture-density relationship for each compaction effort. Along with a speedy moisture tester, dry density can be predicted using target Iv values in a fast and efficient manner based on current standard specification.

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Modeling the non-destructive control of road surfaces compaction

Journal of Physics Conference Series ◽

10.1088/1742-6596/1399/4/044094 ◽

2019 ◽

Vol 1399 ◽

pp. 044094

Author(s):

A P Prokopev ◽

Zh I Nabizhanov ◽

V I Ivanchura ◽

R T Emelyanov

Keyword(s):

Road Surfaces ◽

Non Destructive

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Luminescence from individual dislocations in II-VI and III-V semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088488 ◽

1991 ◽

Vol 49 ◽

pp. 834-835

Author(s):

J W Steeds

Keyword(s):

Group Iv ◽

Luminescence Properties ◽

Carrier Recombination ◽

Transmission Electron ◽

Wide Range ◽

Basic Physics ◽

Semiconducting Compounds ◽

Diamond Group ◽

Non Destructive ◽

Technological Significance

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

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Forensic Identifications Aided by Scanning Electron Microscopy of Silicone-Epoxy Microreplicas of Calcified and Cornified Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117017 ◽

1975 ◽

Vol 33 ◽

pp. 678-679 ◽

Cited By ~ 3

Author(s):

R.F. Sognnaes

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Forensic Science ◽

George Washington ◽

Epithelial Surface ◽

Extended Application ◽

Tissue Surfaces ◽

Non Destructive ◽

Scanning Electron ◽

Surface Changes

Sufficient experience has been gained during the past five years to suggest an extended application of microreplication and scanning electron microscopy to problems of forensic science. The author's research was originally initiated with a view to develop a non-destructive method for identification of materials that went into objects of art, notably ivory and ivories. This was followed by a very specific application to the identification and duplication of the kinds of materials from animal teeth and tusks which two centuries ago went into the fabrication of the ivory dentures of George Washington. Subsequently it became apparent that a similar method of microreplication and SEM examination offered promise for a whole series of problems pertinent to art, technology and science. Furthermore, what began primarily as an application to solid substances has turned out to be similarly applicable to soft tissue surfaces such as mucous membranes and skin, even in cases of acute, chronic and precancerous epithelial surface changes, and to post-mortem identification of specific structures pertinent to forensic science.

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