Scanning electron microscopy clays

Analytical studies, using scanning electron microscopy and electron microprobe techniques (see Textbox 10), revealed that the mixture used for making this particular type of ceramic material consists mainly of clay, comminuted... 

Mullite is almost twice as abundant in low-Ca fly ash when compared to high-Ca fly ash, mainly due to differences in the Al content of the clay minerals associated with the coal (McCarthy et al. 1990). Using atomic absorption spectroscopy (AAS) and scanning electron microscopy /electron microprobe analyses (SEM/ EMPA) Stevenson Huber (1987) found a correlation between the elemental composition of ash particles and the clay mineral species in the raw coal. They concluded that the geologic origin of the coal had a significant impact on the microchemical composition of the ash. 

The mineralogical composition of Sahara dust particles shows the predominance of aluminosilicates (clays). Illite is also present in many cases while quartz particles are rare. Scanning Electron Microscopy (SEM) results on dust composition transported over different regions in the Mediterranean Basin have shown that Al-rich clay minerals such as illite and kaolinite are very common in PM10 for Cypms and dominant for Crete. Dust particles are also very rich in calcium which is distributed between calcite, dolomite and sulphates and Ca-Si particles (e.g. smectites) whereas iron oxides are often detected [43]. 

Laird, D. (2001). Nature of clay-humic complexes in an agricultural soil II. Scanning electron microscopy analysis. Soil Sci. Soc. Am. I. 65,1419-1425. 

Wallace WE, Harrison J, Keane MJ, et al. 1990. Clay occlusion of respirable quartz particles detected by low voltage scanning electron microscopy-X-ray analysis. Ann Occup Hyg 34 195-204. 

The content of acid-soluble iron in paper is determined by TAPPI standard T434 (iron combined in clay and other complex compounds is presumed to be nonreactive). The presence of iron can be shown by the color produced upon wetting the paper briefly with warm 6N hydrochloric acid and then adding a solution of potassium ferrocyanide or thiocyanate localized specks of iron or rust are indicated by the more intense color formation. Complete analysis of paper for metallic elements has been accomplished by chemical procedures, emission spec-trography, scanning electron microscopy/x-ray, and neutron activation. 

Using transmission electron microscopy the lattice fringe image can be seen. Also the scanning electron microscopy image showed that the montmoriilonite layer structures still remained after Si-heterostructure and no occluded clay by SiOj is observed. The results further indicate the expansion of the basal spacing. 

Chen, Y., and Schnitzer, M. Scanning electron microscopy of a humic acid and of a fulvic acid and its metal and clay complexes. Soil Soc. Am. Proc. 40, 682-686,... 

Figure 8.5 Varnish micromorphology form ranges from botryoidal to lamellate (A and C). Two types of imagery show botryoidal varnishes from Kitt Peak, Arizona (A) the topography by secondary electrons (B) the same structures from the bottom upwards with back-scattered electrons - showing the layering structures inside each nudeation centre. (C and D) Scanning electron microscopy images of lamellate clay minerals accreting on rock varnish in Death Valley, California. (C) Individual clay platelets overlap as they cement onto the surface. (D) The clays impose a lamellate structure in cross-section, as first noticed by Potter and Rossman (1977).

McHardy, W.J. Birnie, A.C. (1987) Scanning electron microscopy. In Wilson, M.J. (Ed.) A Handbook of Determinative Methods in Clay Mineralogy. New York Chapman and Hall, pp. 174-208. 

It is common practice to make a distinction between the inorganic constituents of so-called "Eastern" and "Western" coals By definition. Western coals are those for which the CaO+MgO content exceeds the Fe203 content of the ash, while the reverse is true for Eastern coals [ 1 I The inorganic constituents in Eastern coals, which are principally bituminous in rank, are predominantly in the form of discrete mineral particles. Clay minerals (kaolinite, illite) are usually dominant, followed by quartz and pyrite. The range and typical values of the mineral distribution and ash chemistry of Eastern coals are shown in Table I. These data were determined from computer-controlled scanning electron microscopy (CCSEM), Mossbauer spectroscopy, and other measurements on over a hundred coals. 

A combination of techniques, such as powder X-ray diffraction (XRD) [56, 58], thermogravimetric analysis (TGA) [57], differential thermal analysis (DTA) [57], X-ray photoelectron spectroscopy (XPS) [56, 58], scanning electron microscopy (SEM) [26, 57], Fourier transform infrared (FT-IR) spectroscopy [57, 58] and BET N2 adsorption measurements [67], was used for structural characterization of the enzyme-clay conjugates. 

Delage, P., Tessier, D. Audiguier, M.M. (1982). Use of the cryoscan apparatus for observation of freeze-fractured planes of a sensitive Quebec clay in scanning electron microscopy. Can. Geotech. J 19 111-114. 

In Reference 107, the effect of grafting of a polar group (MAH) onto LDPE chains and the chemical modification of clay particles with 2,6-diaminocaproic acid (L-lysine monohydrochloride) to produce nanocomposites with a matrix composed of a ternary blend of PEs (LDPE, LLDPE, and HDPE) was studied in detail. X-ray diffraction was used to determine the exfoliation degree of the clay. Morphological features were revealed by scanning electron microscopy and thermal analysis disclosed the thermal stability of the samples. Comparative analyses of the mechanical (under tension) and rheological properties of the nanocomposites were carried out as well. 

The degree of clay dispersion in a PS matrix was characterized by x-ray diffraction analysis (XRD), and electron microscopy that is, scanning [with field emission gun scanning electron microscopy (FEGSEM)] and transmission (TEM) the results are listed in Table 14.1. The XRD scans were obtained at a scan rate 0.3°/min. The specimens were prepared by compression molding at T= 200°C and a compressive... 

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