Embedding in epoxy resin

Figure 2 shows STEM images of a 8%wt Pd/2%wt Pt catalyst which is supported on charcoal. The sample was prepared for microscopy by embedding in epoxy resin and sectioning with a diamond knife in an ultramicrotome, and was examined in a Vacuum Generator s Ltd HB5 STEM, with a 5A probe. The sample thickness is about 500A. 

Fig. 13.3.7 Typical SEM photographs of a bare polyethylene surface and silica arrangements, embedded in epoxy resin after fracture (a and d) detached silica (0.3 p,m) arrangement after fracture (b) silica (0.3 p,m) arrangement before fracture (c) bare polyethylene surface after fracture (10 p,m).

In TEM, thin sections of samples are embedded in epoxy resins or, alternatively, platinum-carbon replicas of the samples are produced in order to the avoid release of vapor or gases. 

After the last experiments, the rats are euthanized by injection of an overdose of pentobarbital and then perfused intracardially with a phosphate-buffered 2.0% paraformadehyde - 2.5% glutaraldehyde fixative. Methyl green solution was injected to confirm the location of the catheter after the perfusion. The spinal cord and nerve roots were dissected out and immersed in the same fixative for 4 h. Two specimens (10 mm rostral and caudal to the conus medullaris from each rat were postfixed with cacodylate-buffered 1 % osmium tetroxide dehydrated in a series of graded alcohol solutions, and embedded in epoxy resin. From the embedded tissue, 1-pm transverse sections were obtained and stained with toluidine blue dyes. Sections obtained from 10 mm rostral to the conus (caudal spinal cord) were used for qualitative evaluation. Quantitative analysis of nerve injury was performed using the sections obtained form 10 mm caudal to the conus. Each fascicle present in the cross section was assigned to an injury score 0 to 3. The injury score for each cross section was then calculated as the average score of all fascicles present in the cross section. 

Zeolite single crystals may serve as zeolite membrane models. We mention the early elegant work of Hayhurst and Paravar [10] on an oriented large silicalite-1 crystal embedded in epoxy resin. 

Several plagioclasc grains from annealed samples as well as shock-loaded run products were embedded in epoxy resin and polished. Observation was performed with an optical microscope using reflected and transmitted light Major and minor element compositions were determined by an electron probe microanalyzer. Shock textures were also examined in detail with a scanning electron microscope using back-scattered electron images. 

Scanning force microscopy (SFM) has been widely used for visualization of biomedical objects because of combination of extreme resolution, simplicity of sample preparation and ability to operate under physiological conditions. Nowadays SFM is increasingly applied to investigate the ultrastructure of biomedical samples embedded in epoxy resin [1]. In the present work, we are focusing on application of SFM, confocal laser scanning microscopy and ultramicrotomy to the K562 leukemic cells study. 

The aim of this study is to apply SFM combined with confocal laser scanning microscopy to investigate K562 cells surface morphology in details. Also an attempt was made to visualize with SFM the internal ultrastructure of embedded in epoxy resin of K562 leukemic cells. 

Figure 3. SFM image of the internal ultrastructure of embedded in epoxy resin of K562 cell.

Fig. 3 shows SFM image of one of the sections (thickness of - 100 nm) of K562 cell embedded in epoxy resin. It should be noticed that topographical contrast and the identification of the K562 internal ultrastructure critically depend on the procedure of cell preparation before embedding (chemical fixation or high-pressure freezing and freeze-substitution). 

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. 

Fig. 4. Electron micrographs of L-Asp-LI and L-GIu-LI in hippocampus CAl from a hypoglycemic rat subjected to perfusion fixation. The tissue was treated with uranyl acetate before embedding in epoxy resin. The figure shows accumulation of immunoreactivities over synaptic vesicle clusters (sv) versus over cytoplasmic matrix (cm) in terminals making asymmetrical synapses on spines (s). Broken lines mark the houndary between the vesicle-rich and vesicle-poor parts of the terminals. Scale bar = 0.2 pm. (Modified from Gundersen et al., 1998.)...

There are two different ways to perform electron microscopic immunocytochemistry pre-embedding and postembedding (Stirling, 1990). Pre-embedding electron microscopic immunocytochemistry applies the antibodies and label to samples just after fixation but before embedding in epoxy resin and sectioning. Postembedding electron microscopic immunocytochemistry applies antibodies and label to thin sections made after the samples have been embedded in epoxy resin and sectioned. 

Postembedding electron microscopic immunocytochemistry - a method that uses antibodies applied to sections after embedding in epoxy resin and sectioning with an ultramicrotome. 

The influence of coating on mechanical properties of uncoated and coated carbon fibres, embedded in epoxy resin and polycarbonate matrix, respectively, were conducted by a three point bend test applied to the composites. 

For transmission electron microscopy (TEM), gel samples were dehydrated in acetone, stained with osmium tetroxide, and embedded in epoxy resin. The embedded samples were cut into slices of 50-100nm thickness with an ultramicrotome LKB-V (LKB, Sweden) and examined using TEM (Hitachi H-600, Japan). 

Carbon fibers have been used for array construction because they are more rigid than gold. The construction of carbon fiber arrays consisting of five layers of 20 electrodes was introduced by Caudill et al. (29) and used as a flow rate independent amperometric detector. Sleszynski et al. (25) reported the design of ensembles based on reticulate vitreous carbon embedded in epoxy resin. 

The impact impression of the shot was observed under an optical microscope. After the macro-indentation test, a part of specimen surrounding the indentation was cut out, embedded in epoxy-resin, sectioned and had the sectional face ground and polished with abrasive (Buehler s Colloidal Silica). The surface was observed under the optical microscope in the bright field and through the differential interference, a scanning electron microscope (SEM Hitachi s-4000), and an electron probe surface analyzer (EPSA Elionix ERA8000). 

Figure 10 David s star, composed of diamonds embedded in epoxy resin.

Figure 2 Photograph of monopolar receiver. This disk shaped device contains the electronic circuitry embedded in epoxy resin and coated with silicone rubber. The electrical connector is attached to the phrenic nerve electrode. Source From Avery Biomedical Devices.

The use of resins in conjunction with polypyrrole- or polyaniline-coated fabrics yields composite structures that protect the conductive polymer from oxygen and therefore imparts additional stability to these conductive fabrics. Polypyrrole-coated quartz fabrics embedded in epoxy resins have shown sufficient stability in accelerated aging tests, equivalent to 10 years exposure in the field, to be used in the wings of military aircraft [44]. 

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