Instrumentation scanning electron microscopy

Armstrong, J.T., Methods of quantitative analysis of individual microparticles with electron beam instruments, Scanning Electron Microscopy/1978, 1, 455, 1978. 

Instrumentation Scanning electron microscopy. X-ray diffraction, Raman spectroscopy... 

Scanning Electron Microscopy images of powders used in this paper were taken using JEOL s JSM-6320F instrument at the Illinois Institute of Technology and at Drexel University, Philadelphia, PA, USA. 

Instrumentation, image formation, accessories, and applications of conventional scanning electron microscopy will be discussed. Information about the ESEM will also be presented. 

Immunolabel samples either before or after fixation. Any size gold can be used for scanning electron microscopy. The size of the gold particles is limited by the resolution of the instrument. 

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. 

Because of the instrumental requirements, these are usually not routine monitoring techniques. However, unlike other methods, they give detailed information on particle shapes. In addition, chemical composition information can be obtained using transmission electron microscopy (TEM) or scanning electron microscopy (SEM) combined with energy-dispersive spectrometry (EDS). The electron beam causes the sample to emit fluorescent X-rays that have energies characteristic of the elements in the sample. Thus a map showing the distribution of elements in the sample can be produced as the electron beam scans the sample. 

Scanning electron microscopy (SEM) utilizes a highly focused electron beam which is scanned over the surface of the specimen. Since penetration through the specimen is not essential for this instrument, thicker samples (cm range) and lower accelerating potentials (low kV range) are commonly used. The most popular mode of operation is the emissive mode which utilizes those electrons that have either been emitted by the... 

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. 

Figure 13.11—Scanning electron microscopy (SEM) accompanied by X-ray fluorescence analysis. Secondary electron image of a cross-section of a supraconducting polycrystalline ceramic with oriented grains of oxide BiPbiSriCaiCurO, (Philips instrument, model XL30FEG). Energy emission spectra corresponding to the matrix and to a 5 pm-long inclusion (bottom). It should be noted that it is possible with this technique to obtain the composition at a precise point on the sample (Link-Oxford analyser) (study by V. Rouessac, reproduced by permission of CRISMAT. University of Caen).

However, the technique has by no means displaced conventional scanning electron microscopy and indeed has not generated an extensive body of literature demonstrating the unique capabilities of this technology. Currently we are aware of only one manufacturer of the instrument and the number of published papers found is quite small. The reasons for this are not clear. 

The sizing methods involve both classical and modem instrumentations, based on a broad spectrum of physical principles. The typical measuring systems may be classified according to their operation mechanisms, which include mechanical (sieving), optical and electronic (microscopy, laser Doppler phase shift, Fraunhofer diffraction, transmission electron miscroscopy [TEM], and scanning electron microscopy [SEM]), dynamic (sedimentation), and physical and chemical (gas adsorption) principles. The methods to be introduced later are briefly summarized in Table 1.2. A more complete list of particle sizing methods is given by Svarovsky (1990). 

Modern surface analytical tools make it possible to probe the physical structure as well as the chemical composition and reactivity of interfacial supramolecular assemblies with unprecedented precision and sensitivity. Therefore, Chapter 3 discusses the modern instrumental techniques used to probe the structure and reactivity of interfacial supramolecular assemblies. The discussion here is focused on techniques traditionally applied to the interrogation of interfaces, such as electrochemistry and scanning electron microscopy, as well as various microprobe techniques. In addition, some less common techniques, which will make an increasing contribution to supramolecular interfacial chemistry over the coming years, are considered. 

Electron microscopy56, most commonly employed as scanning electron microscopy (SEM), is now a widely used tool in examining the morphology of surfaces under vacuum conditions, and so in an electrochemical context electrode surfaces and corroded surfaces. Instruments also permit chemical microanalysis to be carried out. 

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