Optical microscopy/micrograph

Fig. 7 Evolution of the spherulitic structure of PP with increasing amounts of calcium pimelate (from 0 to 2000 ppm) leading to increasing amounts of -modification as observed by optical microscopy. Micrographs (425 x 650 rm) kindly provided by J. Wolf-schwenger...

Barry, Clinton Wilson (1979) examined the structure of cements prepared from a glass powder from which very fine particles had been removed to improve resolution. The microstructure of the set cement is clearly revealed by Nomarski reflectance optical microscopy (Figure 5.14). Glass particles are distinguished from the matrix by the presence of etched circular areas at the site of the phase-separated droplets. The micrograph... 

Recent developments have allowed atomic force microscopic (AFM) studies to follow the course of spherulite development and the internal lamellar structures as the spherulite evolves [206-209]. The major steps in spherulite formation were followed by AFM for poly(bisphenol) A octane ether [210,211] and more recently, as seen in the example of Figure 12 for a propylene 1-hexene copolymer [212] with 20 mol% comonomer. Accommodation of significant content of 1-hexene in the lattice allows formation and propagation of sheaf-like lamellar structure in this copolymer. The onset of sheave formation is clearly discerned in the micrographs of Figure 12 after crystallization for 10 h. Branching and development of the sheave are shown at later times. The direct observation of sheave and spherulitic formation by AFM supports the major features that have been deduced from transmission electron and optical microscopy. The fibrous internal spherulite structure could be directly observed by AFM. 

Fig. 6.11 Optical microscopy of the surface lary forces during drying of propanol [Lei 9]. of a 25 pm thick micro PS layer on the Si sub- (c) SEM micrograph of a disintegrated micro strate, showing (a) crack formation in the wet PS film formed at high current density...

In the present example polydimethylsiloxane (PDMS) is deposited from an iso-propanol solution onto a glass surface [49], Due to the small amount of PDMS deposited by this technique, with optical microscopy the sample surface appears structureless. For the optical micrograph shown in Fig. 10b we selected a position which exhibits small dust particles by purpose, to demonstrate that the surface was focused. By optical microscopy the untreated and the nano-structured glass surface are indistinguishable. 

Optical microscopy offers an interesting possibility to characterize the /i-phase, as a result of the differences in birefringence between the / -and a-crystals [93]. Its use will be highlighted in different sections of this manuscript. Although image analysis could provide some semi-quantitative information about the amount of the /l-fraction, the optical micrographs are generally evaluated qualitatively by the eyes of a man-of-the-art as control for the WAXS/DSC data. 

Figure 25. Electron micrographs showing three typical views of a water4n-oil emulsion by direct observation. The resolution and depth of field are significantly better than can be achieved via optical microscopy.

Studies by optical microscopy of the material left after evaporating the benzene show a variety of what appear to be crystals—mainly rods, platelets and star-like flakes. Figure 1 shows a micrograph of such an assemblage. All crystals tend to exhibit six-fold symmetry. In transmitted light they appear red to brown in colour in reflected light the larger crystals have a metallic appearance whereas the platelets show interference colours. The platelets can be rather thin and are thus ideally suited for electron-diffraction studies in an electron microscope (see the inset in Fig. 3). 

Major results. The method is useful for control of expensive materials in responsible applications, such as, for example, materials used in aeronautics. Material control or inspection can be conducted (pulse method) without damage caused to the inspected material. The other essential advantage of the method is related to the fact that fillers can be observed within the filled material, which is not possible by any other technique. In addition, clarity of the micrograph is improved compared with optical microscopy. This method, although unique, has many applications in filled materials and hopefully more data will be known in the future in order to facilitate better understanding of filled materials. 

To evaluate the effect of the graded structure on thermal stress, the cross section of the bonding interface of samples was examined. The micrographs by optical microscopy are shown in Photo. 3. Cracks were found near the interface in the cemented carbide of the sample sinter- bonded with single layer of WC- 10%Co. There are no cracks in the samples sinter- bonded with graded cemented carbide and single layer of WC- 15%Co, however. 

Figure 19. Micrographs of a tapered fiber probe for illumination mode scanning near-field optical microscopy. The upper two panels are optical micrographs with light emeig-ing from the aperture. The electron micrograph in die lower panel shows the apex of the tip with the aluminum coating.

Optical microscopy using polarized light gives a first hint on the crystallinity of the obtained structures. A typical result of optical micrographs obtained without polarization, parallel and perpendicular orientation of the polarizer and analyzer are shown in the Fig. 4. If the relative position of the polarizer and analyser is changed the different regions of the spherulites change their colour, while the... 

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