EDX spectroscopy

Figure 3 - Secondary electron image and EDX spectroscopy map showing the presence of elemental gold...

Lindner et al. carried out detailed studies on the use of the sol-gel procedure to obtain new materials as suitable matrices [45]. A co-condensation of Si(OR)4, Si(OR)3-spacer-Si(OR)3 and Si(OR)3-spacer-ligand resulted in new hybrid materials, the properties of which strongly depended upon the spacer and the ratio of the different components used. Most of these materials were characterised with IR, EXAFS, and EDX spectroscopy, scanning electron microscopy and solid state NMR spectroscopy. Solid state 31P NMR was used to quantify the mobility of the interphases the changes in line-... 

The phases, microstructure and chemical composition at the sink side of the PEVD system were studied before and after the PEVD process by x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) spectroscopy, respectively. 

In order to better elucidate the precise structure of the Fe-Ceo compound, high-resolution transmission electron microscopy (HRTEM) and energy dispersive x-ray (EDX) spectroscopy were performed with a field emission microscope. As shown in Fig. 3, the study revealed areas in the sample, highlighted by pink circles, which were consistent with small quantities of oxidized iron in the phase Fe203. The sample was exposed to air as the complex... 

It is now possible to obtain scanning transmission electron microscopes (STEMs). With a STEM, the electrons pass through the specimen but, as in SEM, the electron optics focus the beam into a narrow spot that is scanned over the sample in a raster. This makes these microscopes suitable for analysis techniques such as mapping by energy dispersive X-ray (EDX) spectroscopy among others. Also, the resolution on the latest STEM instruments is less than one Angstrom. 

The catalyst l%Pd Au/C (2) was characterised by TEM, HRTEM and EDX spectroscopy. The observations on the morphology and the microstructures of both the phase and the composition highlight its single phase property. The overview of the catalyst (Fig. 1) shows that the nanoparticles are evenly distributed on the active carbon. The inserted histogram of particle size distribution indicates that most particles are smaller than 10 nm in size. The size distribution is described by a Gaussian function centered at 3.4 nm, with 2 % particles oversized (from 10 nm up to 30 nm). 

STEM is a type of TEM. In this type of microscopy, the electron beam is focused to a narrow spot, which is scanned over the sample. The scanned electrons traverse the samples as in CTEM. Using this technique, several analyses such as mapping by EDX spectroscopy, EELS, and annular dark-field (ADE) imaging can be performed. Both types of information, image and quantitative data, can be obtained. It is noteworthy that STEM imaging provides information from a volume of the material, and therefore in the case of Aims, it provides information on the membrane thickness [49]. 

Scanning electron microscopy (SEM) images and results of the eneigy dispersive A-ray (EDX) spectroscopy were obtained on the JEOL JSM-6400 microscope. The parallel beam of electrons with energy 3 kV was used for X M-image acquisition of the samples surface, while under the qualitative and quantitative determination of elements in the samples the eneigy of electrons (EHT) was scanned in the 0-10 kV interval. In the first case the distance from electron source to samples surface was 3-4 mm, while during EDX studies - 10 mm. 

The methods of extracting chemical information from a core-loss EEL spectrum are analogous to that in energy-dispersive X-ray (EDX) spectroscopy. The... 

Moreover, EELS is very sensitive to light elements that are problematic in EDX spectroscopy. This makes EELS an interesting technique to study, for instance, organic materials. 

Energy-dispersive X-ray (EDX) spectroscopy utilizes the characteristic spectrum of X-rays that is emitted by a sample, following initial excitation by the high-energy electron beam. Information about the elemental composition of the sample can be obtained, where the spatial resolution is determined by the probe size, any beam broadening occurring within the specimen, and the effects of any backscattered electrons on the specimen around the point of analysis. EDX is relatively simple and can be used to provide rapid qualitative microanalysis. Quantitative elemental analysis can also be achieved, with an... 

Leonard (1977) traced the transformation sequence kaolinite-metakaolinite-spinel-muUite by studying the radial electron density (RED) distribution of kaolinite and its transition products as a function of temperature, and correlated the results with chemical information obtained with X-ray fluorescence spectroscopy. While the presence of some Si-Al spinel could not completely be ruled out, most of the A1 atoms were found in the configuration of y-Al203 beyond a firing temperature of 900°C. This assumption was corroborated by Sonuparlak et al. (1987), who showed by transmission electron microscopy (TEM) in conjunction with energy-dispersive X-ray (EDX) spectroscopy that the spinel phase formed at 980 °C, indicated by a strong exothermic DTA peak, contains <10 mass% Si02, if any. 

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