Transmission electron microscopy embedding

The picture of cement microstructure that now emerges is of particles of partially degraded glass embedded in a matrix of calcium and aluminium polyalkenoates and sheathed in a layer of siliceous gel probably formed just outside the particle boundary. This structure (shown in Figure 5.17) was first proposed by Wilson Prosser (1982, 1984) and has since been confirmed by recent electron microscopic studies by Swift Dogan (1990) and Hatton Brook (1992). The latter used transmission electron microscopy with high resolution to confirm this model without ambiguity. 

III. Transmission electron microscopy of radish seeds Transmission electron microscopy (TEM) of radish seeds was done as listed below For TEM preparations, the specimens after fixation and dehydration, were embedded in Epon 812 resin (Luft, 1961). Thick sections (ca. 1mm each) were stained with 0.1% toluidine blue and observed with a Zeiss light photomicroscope. Thin sections, obtained with a diamond knife on a Supernova microtome, were sequentially stained at room temperature with 2% uranyle acetate (aqueous) for 5 min and by lead citrate for 10 min (Reynolds, 1963). Ultrastructural studies were made using a Philips CM12 transmission electrone microscope (TEM) operated at 80 KV. 

Chemical fixation for transmission electron microscopy prepares cells for the preservation of damage due to subsequent washing with aqueous solvents, dehydration with organic solvents such as ethanol or acetone, embedding in plastic resins, polymerization of the resins by heat, exothermic catalysts, or ultraviolet radiation, and imaging with high-energy electron beams in an electron microscope. 

Table 4 Resins Commonly Used for Embedding Plant Tissues for Transmission Electron Microscopy ...

FIGURE 1.1. Electron micrographs of liver tissue processed differently for transmission electron microscopy. (A) Processed by the conventional method. Note superior quality of ultrastructural preservation compared with that obtained with microwave heating. (B) Rapidly processed by vacuum microwave heating. The whole process from tissue fixation to resin embedding was completed in 2 hr. The quality of ultrastructural preservation is satisfactory. Magnification 6,21 Ox (B). (B) courtesy of Richard T. Giberson. 

Wang NS, Minassian H. (1987) The formaldehyde-fixed and paraffin-embedded tissues for diagnostic transmission electron microscopy a retrospective and prospective study. Hum. Pathol. 18, 715-27. 

Figure 12.2. The structure of ice cream mix and ice cream. (A). Fat globules (F) in mix with crystalline fat within the globule and adsorbed casein micelles (C), as viewed by thin section transmission electron microscopy. (B). Close-up of an air bubble (A) with adsorbed fat, as viewed by low temperature scanning electron microscopy. (C). Air bubble (A) with adsorbed fat cluster (FC) that extends into the unfrozen phase, as viewed by thin section transmission electron microscopy with freeze substitution and low temperature embedding.

Fig. 7. The effect of adsorbed protein on structure of ice-cream mix, ice cream, and melted ice cream. A-B, ice-cream mix with no surfactant and with added surfactant, respectively, as viewed by thin-section transmission electron microscopy. f= fat globule, c = casein micelle, arrow = crystalline fat, bar = 0.5 pm. See Reference 24 for methodology. C-D, ice cream with no surfactant and with added surfactant, respectively, as viewed by low-temperature scanning electron microscopy, a = air bubble, f = fat globule, bar = 4 pm. See Reference 34 for methodology. E-F, ice cream with no surfactant and with added surfactant respectively, as viewed by thin-section transmission electron microscopy with freeze substitution and low-temperature embedding. a = air bubble, f= fat globule, c = casein micelle, fc = fat cluster, bar = 1 pm. See Reference 13 for methodology. G-H, melted ice cream with no surfactant and with added surfactant respectively, as viewed by thin-section transmission electron microscopy. f= fat globule, c = casein micelle, fn = fat network, bar = 1 pm in G and 5 pm in H. See Reference 24 for methodology.

TEM (Transmission Electron Microscopy) analysis. This analysis was done on a Philips 420T microscope (120kV, maximum resolution 5A) equipped with an EDAX PV9900 EDS. The catalysts were ground to a powder, embedded in epoxy resin and then microtomed with a diamond l fe to obtain sections about 300A thick. Images were taken at 100 kV. Diameters of about 100 isometric-shaped Pt crystallites were measured for each sample. 

The characterisation of the colloids both in the free and in the embedded state was first performed using transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), and atomic absorption spectroscopy (AAS). In addition, nitrogen adsorption-desorption curves at 77 K, H2-chemisorption measurements, solid state Si-NMR, XRD, SAXS, XPS, MAS-NMR, NH3-FTIR, and Au Mossbauer spectroscopy were applied. For the embedded triflates, the catalysts were characterized by nitrogen adsorption-desorption isotherms at 77K, TG-DTA, H, C, and Si solid state MAS-NMR, XRD, TEM, SEM, XPS and, FTIR after adsorption of NH3. 

Fig. 1.9. Dislocation core in A1 as seen experimentally using high-resolution transmission electron microscopy (a) and image simulation of results of atomistic simulation using embedded-atom potentials (b) (adapted from Mills et al. (1994)).

The samples have been prepared by e-beam evaporation of a dielectric layer followed by thermal evaporation of the silver fraction, which builds the island film, while the sandwich is completed by a further dielectric film. In every sample, intentionally the same amount of silver (corresponding to an average thickness of 4 nm, as recorded by quartz monitoring) has been embedded in a 6 nm thick dielectric film, formed from either Mgp2, LaFs, Si02, or AI2O3. The optical transmittance T and reflectance R of all films have been measured by a Perkin Elmer Lambda 19 spectrophotometer. To correlate the optical properties with the sample morphology, transmission electron microscopy (TEM) has been applied. 

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to study the morphology and microstructure of carbon-Ti02 composites. In the case of CNT-Ti02 composites, observations on CNT embedded in Ti02 matrix [111,115] and fine coating of Ti02 on a CNT surface [107,112-114,116,117] are reported. 

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