Scanning radiography

In case of some samples besides the cross sectional CT-slice also a projectional image is of interest. In these cases the test mode Digital Radiography (DR) is applied. In the DR-mode the object is not turned, but scanned horizontally and vertically. Again the very high dynamic of the detector and the mechanical accuracy of the complete system are of large benefit to the image quality. 

There ate four main approaches to x-ray imaging contact radiography, scanning x-ray microscopy, holographic x-ray microscopy, and shadow projection x-ray microscopy. In the future, there will likely be phase-contrast imaging and photoelectron x-ray microscopy. 

The authors wish to acknowledge the work of Paul McCarthy in scanning electron microscopy, Michael Saculla in x-ray radiography, and Steven Buckley and Chuck Chen in sample preparation and modulus measurement. This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48. 

Fig. 11. Schematic of neutron resonance radiography system. The object being scanned moves around the target the neutron energy changes with angle scanning each pixel of the object at multiple energies.

For soft human tissue that would be otherwise have too low a contrast to be resolved in conventional high-intensity planar X-ray radiography, a thorough study of X-ray absorbance as a function of tissue density and thickness allowed the development of hardware and software for computed axial tomography (CAT scanning) which performs a three-dimensional analysis of X-ray absorption at low intensities and convenient two-dimensional displays of resolved human tissue features. 

The distribution of the substance in the body is often studied with substances that have carbon-14 as a radioactive label in the molecule. The labeled substance must be specifically S3mthesized, but it allows a direct visualization of the distribution in the animal body. In a process called whole body radiography, thin slices of the dead deep-firozen animal are prepared and scanned for distribution of radioactivity. Images of the various two-dimensional slices are then combined to give a three-dimensional pic-tvire. In a parallel experiment, the target organs are isolated and extracted with solvents. The extracts are used to isolate and identify the metabohtes. 

Technical examination of objects coated with a protective covering derived from the sap of a shrubby tree produces information that can be used to determine the materials and methods of manufacture. This information sometimes indicates when and where the piece was made. This chapter is intended to present a brief review of the raw material urushi, and the history and study of its use. Analytical techniques have included atomic absorption spectroscopy, thin layer chromatography, differential thermal analysis, emission spectroscopy, x-ray radiography, and optical and scanning electron microscopy these methods and results are reviewed. In addition, new methods are reported, including the use of energy dispensive x-ray fluorescence, scanning photoacoustical microscopy, laser microprobe and nondestructive IR spectrophotometry. 

Sonoda M., Takano M., Miyahara J., and Kato H. 1983. Computed radiography uthizing scanning laser stimulated luminescence, J. Radiol. 148(3) 833-838. 

This astounding discovery is widely used today and has taken an important place in society. Indeed, X-rays are now used in medicine to detect abnormalities in the human body (radiography, CT, etc.). X-rays are also used to remove cancer cells. Obviously, this practice can also be harmful to healthy cells if it is not used prudently. Also at airports, baggage is scanned by X-ray to identify liquids are other potentially hazardous objects. 

Density homogeneity VLM SEM X-ray radiography/CT scan Ultrasound Die penetration... 

The surface of the samples was examined in two ways by metallurgical microscope Nikon MA200 and scanning microscope Quanta 200 in the low vacuum mode. To identify the structure of the obtained layers the X-Ray radiography was used. Additionally properties of the composites was studied using impedance spectroscopy. The method of impedance spectroscopy allows one to connect the measured frequency characteristics with the physical structure of tested material and the alternations in the structure. This method has been used by the authors to determine the properties of plasma layers deposited on a polypropylene nonwoven fabric (Jaroszewski et al., 2010a Pospieszna et al, 2010 Pospieszna et al, 2010b). 

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