X-ray radiography

The principles of gamma-ray radiography are the same as X-ray radiography except that a radioisotope is used as the radiation source rather than an X-ray tube. 

AH of these properties of x-rays are used to measure various properties of materials. X-ray appHcations can be placed into three categories based on which of the above phenomena are exploited. These categories are x-ray radiography, x-ray fluorescence spectrometry, and x-ray diffraction. 

X-rays were discovered by Wilhelm Roentgen in 1895. Soon after their discovery Roentgen used x-rays to image the bones in a human hand. The x-rays transmitted through the hand (phenomenon 1) were recorded on photographic film. The bones or other dense objects absorb x-rays more than do soft tissues or less dense materials (phenomenon 2). This method of imaging the internal stmcture of an object is known as x-ray radiography. 

X-ray radiography can be used to detect mislocated and damaged details such as blown or crushed core (Fig. 20). It is not useful in detecting voids since the change in X-ray opacity through a void is negligible. 

Molecular and cellular processes were visualized by X-ray contrast agents long before the term molecular imaging became popular and even before the advent of early CT (Table 1). Because of the above-mentioned limitations in the sensitivity of contrast detection by X-ray radiography, the latter can only visualize high capacity transport mechanisms and the nonspecific uptake of particles by specialized cells. 

To remove this interference, an associated technique such as x-ray radiography could be used to iook for copper articles. Also high-maintenance, high-resolution germanium detectors might allow... 

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. 

Manke, Ch. Hartnig, M. Grunerbel, et al. Investigation of water evolution and transport in fuel cells with high resolution synchrotron x-ray radiography. Applied Physics Letters 90 (2007) 174105-1-174105-3. 

X-ray radiography was used to study the failure mechanism and capacity loss due to disintegration of the Al-Li alloy during cycling of the cell Li-Al/KCl-LiCl/Te (79). 

Dept of the Army Technical Manual TM 20— 205(1944) 38a)A.C.VanTine J.L.Corbett, "Inspection of High-Explosive Shell by X-Ray (Radiography of Ammunition),Iowa Ordnance Plant, Burlington,Ia(l944 ) 39) non,... 

X-ray radiography H2O (liquid) High spatial ( 10 p,m) and temporal resolutions are possible Less sensitivity to water, technique still needs refinement... 

When X-rays interact with any kind of materials, absorption and phase shifts effects occur. Conventional X-ray radiography relies on the absorption properties of the sample. The image contrast is produced by a variation of density, a change in composition or thickness of the sample, and is based exclusively on the detection of an amplitude variation of X-rays transmitted through the sample itself. Information about the phase of X-rays is not considered. The main limitation of this technique is the poor intrinsic contrast in samples with low atomic number (i.e., the case of soft matter ) or in materials with low variation of absorption from point to point. 

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