Microradiography

Important features in microscopy are in situ methods, quantitative interpretation of the object microstructure and the definition of 3D information. Of the techniques available to the microscopist today, only transmission X-ray microscopy gives nondestructive high-resolution information from the internal structure of an object under natural conditions. By combining the X-ray transmission technique with tomographical reconstruction 3D information about the internal microstructure can be derived [729], X-ray microtomography (/rCT) requires an X-ray microscanner (8 nm spot size), precision object manipulator. X-ray CCD camera, and microtomographical data processing [730]. 

X-ray projection microscopy and X-ray microtomography were reviewed [729]. The performance of the technique, with CCD detectors and hard X-rays was illustrated. 

X-ray microscopy (XRM) allows non-destructive investigation of the micro-structure (fractures) of plastics, paints, adhesives, and inks. Coatings on surfaces and fibres within composite structures may be studied. Examples of X-ray micrography are the observations of inclusions in paint and ink coatings and surfaces of painted substrates. 

X-ray microtomography has been used for nondestructive imaging of defects (defectoscopy) and imaging of composite materials e.g. fibre reinforced plastic foam) [730]. These examples are results of conventional X-ray imaging with reconstructions based on the density of the object phase-contrast tomography offers additional possibilities. 

Autoradiography was used to show non-uniform distributions of radiolabelled additives in PE, PP and PS [732]. XRM and high-resolution (to 5 jxm) tiCl have allowed 2D and 3D imaging of the non-uniform void and silica-supported chromium catalyst fragment distribution within PE particles [732a]. 

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Rosenqvist, M. (2000). The distribution of introduced acetyl groups and a bnseed oil model substance in wood examined by microradiography and ESEM. International Research Group on Wood Preservation, Doc. No. IRG/WP 00-40169. 

FI G U RE 5.1 Top The principle of microradiography — an x-ray absorption technique for quantitative assessment of dry weight (mass). Bottom In addition to the mass information, a specified element can be quantitatively assessed by using two monochromatic radiation wavelengths on each side of an absorption edge for the element. (Adapted from Lindstrom, B., Acta Radiologica Suppl. 125, 206, 1955.)... 

Microradiography has not yet been used extensively to study archaeological materials. This technique, which allows study of details too fine to be seen with the naked eye by enlarging the x-ray radiograph, may find useful applications in the future. 

Amaechi BT, Higham SM, Edgar WM Use of transverse microradiography to quantify mineral loss by erosion in bovine enamel. Caries Res 1998 32 351-356. 

Arends J, Ruben JL, Inaba D Major topics in quantitative microradiography of enamel and dentin R parameter, mineral distribution visualization, and hyper-remineralization. Adv Dent Res 1997 11 403-414. 

Other methods for assessing erosion in situ include transverse microradiography, where the remineralisation (or further demineralisation) of erosive lesions is studied on enamel blocks cemented to the lingual aspect of the lower incisors [46],... 

Annegarn H J, Jodaikin A, Cleaton-Jones PE, Sellschop JPF, Madiba CCP, Bibby D PIXE analysis of caries related trace elements in tooth enamel. Nucl Instrum Methods 1981 181 323-326. Theuns HM, van Dijk JWE, Jongebloed WL, Groeneveld A The mineral content of human enamel studied by polarizing microscopy, microradiography and scanning electron microscopy. Arch Oral Biol 1983 28 797-803. 

Wilson PR, Beynon AD Mineralization differences between human deciduous and permanent enamel measured by quantitative microradiography. Arch Oral Biol 1989 34 85-88. 

To answer the second question (on inner branching), it is necessary and sufficient to determine whether there are interfaces within a nondendritic grain which strongly differ from the matrix by a content of alloying elements as is typical for dendritic cell boundaries. Methods of isocomposition (see Figure 22), X-ray diffraction, and microradiography were used to solve the problem. 

Coincident with this new technique for procurement of human bone biopsies was the development of quantitive methods of bone analysis.12 These methods include histochemical analysis of both decalcified and unde-calcified42 48 bone sections, microradiography,44 tetracycline labeling45 and autoradiography.42 The latter two techniques require administration of a tetracycline antibiotic or isotopic tracer prior to procurement of the biopsy. Undecalcified thin sections, prepared with the use of a Jung microtome after the bone core is fixed, dehydrated and embedded in methacrylate,45 are analyzed by intersect and point count methods46 47 which permit three-dimensional assessment.48 49 Tetracycline antibiotics deposit in vivo in sites of bone formation constituting markers which can be studied in undecalcified sections by fluorescence microscopy.45 47 This represents the safest and best tissue time marker for microscopic measurement of bone formation dynamics. 

G.14 George L. Clark. Applied X-Rays, 4th ed. (New York McGraw-Hill, 1955). Very comprehensive and oriented toward applications of x-ray diffraction, medical and industrial radiography and microradiography, and chemical and biological effects of x-rays. A wide range of crystal structures is also described. 

G.19 A. Taylor. X-Ray Metallography (New York Wiley, 1961). X-ray diffraction, radiography, and microradiography. Structures of metals and alloys determination of phase diagrams, texture, grain size, and residual stress chemical analysis and studies of ceramics. 

Fiber orientation was determined by microradiography. The images of microradiographs were digitized and their orientational distribution determined by image processing software. The fiber orientation function was calculated from the following equation ... 

A three-electrode electrochemical cell was specifically designed for our in situ microradiography tests. The cell was machined in Teflon and had two windows with adjustable positions to control the solution thickness. A 5 mm thick solution was selected so as to avoid unnecessarily excessive x-ray absorption by the electrolyte while providing an adequate space for ramified growth. The distance between the cathode and the anode was adjusted to 10 mm. 

Cross-sectional microradiography image of the coated Ti6AI4V rod implanted into the femoral medulla of sheep (Heimann, 2006, 2010, 2012). 

Figure 4 X-ray microradiography (A) contact microscopy, (B) projection microscopy, and (C) inline imaging.

Contact X-ray microradiography or X-ray contact microscopy (XCM) has been applied to the largest range of specimens due to its simple implementation and considerable versatility. The biological sciences are the most important field of applications for XCM. The nonlinearity of resists makes the resist-based contact microscopy unsuitable for quantitative imaging, which considerably limits its application to materials science. However, quite opposite to the... 

Industrial radiography (or microradiography) is one of the best known and most common practical... 

Orientation of fibres can be studied by RRIM by contact microradiography. In Fig. 6.12 the polymer matrix shows a typical random distribution. Each individual fibre can be readily seen to be surrounded by a coating of polymer, and exists in a straight needle-like form. Also some fibres are present as undispersed bundles observed by darker circles which represent vertically aligned fibres. 

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