ED Spectra

The XRD spectra for the nonvolatile material produced from the pyrolysis of 7, with the Joint Committee on Powder Diffraction Standards (JCPDS) reference patterns for CuInS2 (27-0159), confirmed it to be single-phase CuInS2 (see Fig. 6.9). Examination of the EDS spectra for the same samples shows predominant emissions from Cu, In, and S edges, with the approximate percentage atomic composition of 27, 23, and 50 for 7 and 28, 23, and 49 for 8, respectively, thus supporting the formation of CuInS2. 

BSEI) showing oxidation of stibnite. (B) SEM/EDS spectra obtained within a secondary oxide (mixture of Fe and Sb oxide). White square is the location of the EDS analysis shown in (B) and SO means secondary oxide. 

Fig. 2. Characteristics of the ochre-precipitates and thermal evolution, a) XRD patterns b) SEM - SE images, showing the morphology of the aggregates and respective EDS spectra.

Fig. 1.7 Representative EDS spectra of Na-montmoriUonite. Cu peaks arise from the TEM grid. Reprinted with permission from Yaron-Marcovich D, Chen Y, Nir S, Prost R (2005) High resolution electron microscopy (HRTEM) structural studies of organo-clay nanocomposites. Environ Sci Technol 39 1231-1239. Copyright 2005 American Chemical Society...

Inorganic analysis was conducted in conjunction with the mineral analysis. Particles analyzed previously for mineral content were analyzed for their inorganic content, and an overall analysis conducted. The resultant EDS spectra output was fed into a spreadsheet software package which was adapted by the authors to allow the calculation of a quantitative elemental analysis. 

EDS results from a number of tablets demonstrated that the Cu inclusions are generally alloys with chemical compositions of bronze and brass. These inclusions also contained variable amounts of lead and arsenic. The inclusions were small enough to make it difficult to determine if the lead was from the lead matrix, or from the inclusion. Tablet AUD-259 was found to have a Sn-Sb alloy. Figure 5 shows the spectra of the largest of these Sn-Sb alloy inclusions. The two elements overlap somewhat on the EDS spectra but a double peak from the strongest lines of each element can be seen. WDS analysis revealed that the alloy is approximately 54% Sn, 43% Sb, 1.5% As, and 1.5% Pb. Silver inclusions are generally pure silver, according to the EDS spectra. 

Just as DENs particle sizes have some distribution (albeit relatively narrow), there is surely some distribution in particle compositions for bimetallic DENs. This is a fundamentally important aspect of DENs, particularly with regard to their catalytic properties however, there are presently no reliable characterization methods for evaluating particle composition distributions. One method that has been applied to PdAu [21] and PtPd [19] DENs, as well as dendrimer-templated PtAu [24] is to collect single particle EDS spectra from several (15-20) nanoparticles. These experiments indicate that individual particle composition distributions may vary widely, but the difficulty in obtaining data from the smallest particles may skew the results somewhat. EDS spectra collected over large areas, which sample tens or hundreds of particles, generally agree well with the bulk composition measurements [24] and with stoichiometries set in nanoparticle synthesis [19,21,24]. 

Analysis schemes developed for identifying clay minerals in the TEM based on EDS spectra (e.g., Murdoch et al.100) are inappropriate for colloidal samples dispersed on polycarbonate filters due to complications associated with the various sample-beam-substrate interactions that differ dramatically from that of ideal samples or standards with smooth polished surfaces.94 96 101 102 Correction procedures that account for the influence of particle size and morphology on x-ray spectra have been widely available for some time,101102 but these techniques have not been applied to the analysis of environmental particulates. To overcome the limitation of quantitative elemental analysis, some research groups have compared the x-ray spectra for sample colloids to the spectra for various minerals of similar size and composition under the same instrumental and sample preparation conditions to calibrate instrumental response.7 24 93 Noting the resolution problems associated with SEM analysis of submicron colloids, several research groups have chosen TEM as the primary discrete particle analysis technique,21 52 103 104 or have combined TEM analysis techniques, such as electron diffraction and x-ray microanalysis, to confirm conclusions drawn from SEM surveys.7,93 105... 

As an example of thin-foil analysis in the SEM, samples of the mineral standard kaolinite (<2 pm fraction, KGa-2, Source Clay Minerals Repository) were dispersed on TEM grids and analyzed using a JEOL JSM 6400 SEM under the control of an automated Noran Voyager EDS system equipped with a thin-window EDS detector.93 For comparison, EDS spectra were also collected using the same instrument for the kaolinite size fractions deposited on polycarbonate filters, fixed to SEM... 

FIGURE 11.11 (a) TEM image, (b) selective-area electron diffraction pattern, and (c) EDS spectra for synthetic Al-substituted goethite. 

Data obtained in the EDS analyses are listed in Table I. The fiber standards (primarily organic ) gave broad EDS spectra. No heavy elemental composition was indicated in silk, and only a small quantity of calcium could be detected in linen. No elemental maps could be obtained for silk or linen. The EDS spectra of wool reflected its sulfur content. In some of the samples, the somewhat higher concentration of sulfur in one-half of the cross section, which is expected of this naturally bicomponent fiber, was apparent (7). In other samples, the differentiation was not clear. 

The (113), (110) and (112) crystal planes on the surface are indicated, (b) HRTEM image of HgBa2Cu04+6 viewed down the [010] direction, showing a disordered coating on the (100) surface. The insets are EDS spectra from the surface area (top left) and the interior area (top right). 

Figure 17 EDS spectra on and off single ferritin molecule. Note fow-Fe K signal and low background when the probe passes through a hole in the sample...

Figure 6. EDS spectra ofPHEMA (A) and PHEMA+Citrate (B) after subcutaneous implantation in rats for 2 months.

Fe,0, as standards. EDS measurements with the TEM cross sections were performed for the Ti and A1 content using the base metal "y-TiAl as standard and EELS was used for measuring the O content because of the overlapping of theTi-L0 and 0-Ka lines in the EDS spectra. 

Fig. 5 SEM micrograph and EDS spectra of the Nb-ZMT ceramics with 10 wt% Bi203 addition sintered at 900°C.

Figure 23.8. Fe° aggregates (from Connelly-GPM Inc., USA) after 6 days of use for treating Cr(VI). (a) SEM photomicrograph of Fe° aggregate with surface precipitates (1500x magnification). (b) Energy dispersive X-ray spectroscopy (EDS) spectra shown for the entire used Fe° aggregate. The semiquantitative results indicate Si 5.28 wt %, Fe 79.86 wt %, O 6.65 wt %, Cr 8.22 wt %.

EDS spectra Graphical plot of peaks identifying elements detected within the area analyzed. The area analyzed can be adjusted to encompass submicrometer or several millimeters. The intensity of peaks (peak height) is related to the elemental concentration. 

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