Scanning electron microscopy gold coating

For the purpose of calibration and particle size calculations, it was decided to confirm the reported particle sizes of the various latices supplied by Dow and Polysciences, using scanning electron microscopy. Unfortunately, after subtracting the thickness of the gold layer with which the particles were coated from the size shown on the micrographs, some inconsistencies were noted with respect to the measured sizes of the particles and their elution behaviour. It was therefore decided to assume the reported sizes as true values with the exception of the 5T nm particle. 

This technique can be applied to samples prepared for study by scanning electron microscopy (SEM). When subject to impact by electrons, atoms emit characteristic X-ray line spectra, which are almost completely independent of the physical or chemical state of the specimen (Reed, 1973). To analyse samples, they are prepared as required for SEM, that is they are mounted on an appropriate holder, sputter coated to provide an electrically conductive surface, generally using gold, and then examined under high vacuum. The electron beam is focussed to impinge upon a selected spot on the surface of the specimen and the resulting X-ray spectrum is analysed. 

Figure 3. Scanning electron microscopy images of gold electrodes coated by the nanostructured TMPP/C12 monolayer after the electrochemical platinum deposition. The deposition charge was 41 and 160Cm for the left and right images, respectively. (Reprinted from Ref [18], 2005, with permission from Wiley-VCH.)...

The scanning electron microscopy micrographs shown in the body of this manuscript were taken by AMR-1000 and Jeol C-35 instruments. All specimens were gold-palladium coated. To obtain the cross-section morphologies, the membranes were fragmented in liquid nitrogen. 

Scanning electron microscopy (SEM) seems to have been used only scarcely for the characterization of solid lipid-based nanoparticles [104], This method, however, is routinely applied for the morphological investigation of solid hpid microparticles (e.g., to smdy their shape and surface structure also with respect to alterations in contact with release media) [24,38,39,41,42,80,105]. For investigation, the microparticles are usually dried, and their surface has to be coated with a conductive layer, commonly by sputtering with gold. Unlike TEM, in SEM the specimen is scanned point by point with the electron beam, and secondary electrons that are emitted by the sample surface on irradiation with the electron beam are detected. In this way, a three-dimensional impression of the structures in the sample, or of their surface, respectively, is obtained. 

Scanning Electron Microscopy, An ISI model Super II (International Scientific Instruments Inc., Milpitas, CA) scanning electron microscope was used for morphology study (Labtech, Fairfield, NJ). Powder was properly loaded on specimen stub via a double stick tape. Samples were coated with 60% gold and 40% palladium for 6 min at 100 to 200 mtorr in a sputter coater. 

Microscopy. Scanning electron microscopy was run on resin samples using a AMR 1200 Scanning Electron Microscope. The samples were mounted on the stub using double stick tape and then sputter coated with gold. 

Scanning electron microscopy is an important tool when examining the mode of wear of any sample. The surface of the sample is coated with a very thin layer (only several atoms thick) of a conductive material such as gold. The surface is scanned using a beam of electrons and the image magnified and recorded. 

Samples of microspheres were mounted on aluminum specimen mounts by means of double-faced tapes. The microspheres were fractured with razor blades to expose the internal matrix. The samples were then coated with approximately 125 of gold by pulsing the sputter coater to avoid the possibility of artifact caused by heat generation. Secondary emissive scanning electron microscopy was performed with an Amray 1600 Turbo scanning electron microscope. 

Fig. 2.2. Mycelium of Hebeloma crustuliniforme after colonization of a potassium feldspar surface for seven months. The sample was prepared by fixation and critical point drying followed by gold coating and analysis by scanning electron microscopy. Hyphae (H) and bacteria (B) are visible. Scale bar = 10 pm. The hyphal surface contact is mediated by a fdm of extracellular mucilage (arrow) and bacteria are seen in the mucilage.

Scanning Electron Microscopy fSEM). An IS1-40 SEM was used to take photomicrographs of cellulose fibers fractured in liquid nitrogen and coated with a gold-palladium alloy. 

Fracture surfaces were examined optically and by scanning electron microscopy (SEM) using an Etec apparatus. Prior to SEM investigation, the fracture surfaces were coated with a thin layer of gold-palladium. 

For scanning electron microscopy, the carhon samples from the middle part of the column were freeze dryed, coated with gold, and viewed under Jeol — JSM-35 SEM. 

Morphology. The morphology of the fracture surface of the two-phase epoxy thermosets was examined by scanning electron microscopy (SEM, Amray model 1000B). SEM specimens were sputter-coated with a thin film of gold. 

Scanning Electron Microscopy (SEM). Samples intended for SEM analysis normally were mounted directly on polished aluminum microscope stubs before irradiation. Several filaments were peeled before mounting to expose the sample interior to UV irradiation as described previously (8). The mounted filament samples were gold coated before examination to minimize charging in the electron beam. A Cambridge S-2 scanning microscope was used for all studies. 

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