Microscopic techniques scanning electron microscopy

The composites as well as the nanowires were characterized by several techniques. Scanning electron microscopy (SEM) images and energy dispersive analysis of x-rays (EDAX) were obtained with a Leica S-440I microscope fitted with a Link ISIS spectrometer. Infrared (IR) spectra were recorded on small pieces of the samples embedded in KBr pellets using a Broker FT-IR spectrometer. DSC was carried out on the samples ( 7 mg) with a scanning rate of 20 K min-1 between 120 and 260 °C using a Mettler-Toledo DSC. 

The morphology of SLN dispersions can be investigated by different electron microscopic techniques. Transmission electron microscopy (TEM) is the most commonly used technique although also e.g. scanning electron microscopy (SEM) was used to study SLN dispersions. ... 

When attempting to see membrane structures below one micrometer the possible microscopic techniques are electron microscopy (EM), which can be supplied by an additional elemental scanning (EDS) device (see Chapter 3). In this case and also in transmission electron microscopy (TEM) [7] the samples need to be dry. It is often quite difficult to study polymer membranes with these microscopic techniques because the densities of most materials are the same. Therefore, marker systems should be used like radioactive tracers, fluorescent staining or dendrimeric staining. Today, in environmental scanning electron microscopy (ESEM) one can work also with wet samples. 

The interface properties can usually be independently measured by a number of spectroscopic and surface analysis techniques such as secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy (XPS), specular neutron reflection (SNR), forward recoil spectroscopy (FRES), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), infrared (IR) and several other methods. Theoretical and computer simulation methods can also be used to evaluate H t). Thus, we assume for each interface that we have the ability to measure H t) at different times and that the function is well defined in terms of microscopic properties. 

Scanning electron microscopy is commonly used to study the particle morphology of pharmaceutical materials. Its use is somewhat limited because the information obtained is visual and descriptive, but usually not quantitative. When the scanning electron microscope is used in conjunction with other techniques, however, it becomes a powerful characterization tool for pharmaceutical materials. 

Microscopic techniques, 70 428 Microscopists, role of, 76 467 Microscopy, 76 464-509, See also Atomic force microscopy (AFM) Electron microscopy Light microscopy Microscopes Scanning electron microscopy (SEM) Transmission electron microscopy (TEM) acronyms related to, 76 506-507 atomic force, 76 499-501 atom probe, 76 503 cathodoluminescence, 76 484 confocal, 76 483-484 electron, 76 487-495 in examining trace evidence, 72 99 field emission, 76 503 field ion, 76 503 fluorescence, 76 483 near-held scanning optical,... 

In addition to surface analytical techniques, microscopy, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning tunneling microscopy (STM) and atomic force microscopy (AFM), also provide invaluable information regarding the surface morphology, physico-chemical interaction at the fiber-matrix interface region, surface depth profile and concentration of elements. It is beyond the scope of this book to present details of all these microscopic techniques. 

Aerosol Heterogeneity. The variation of the chemical composition from particle to particle within an aerosol size class has been probed in a number of ways. Single-particle chemical analysis has been achieved by using the laser Raman microprobe (25) and analytical scanning electron microscopy (26). With the electron microscope techniques, the particle can be sized as well as analyzed chemically, so the need for classification prior to sample collection is reduced. Analyzing hundreds to thousands of particles provides the information necessary to track the particles back to their different sources but is extremely time consuming. 

In research on the mechanisms gouverning the modification reactions, the thin silica layers allow the application of various surface analytical techniques, which are of no use for analysis inside porous systems. Reaction mechanisms are simplified by the elimination of porosity and may be studied by direct surface techniques such as ellipsometry, as well as microscopic techniques such as Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).59... 

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