Zirconium surface distribution

Figure 2 The surface distribution of (A) aluminum, (B) gallium, and (C) zirconium and hafnium from coastal to open ocean regions in the North Pacific and western North Atlantic. Note the scale changes between oceans. In all panels, the coastal locations are plotted at the outside edges, with more oceanic locations in towards the middle. The data for Al and Ga in the eastern North Pacific are from 28°N 155°W to 36°N 123°W (Orians and Bruland, 1986, 1988b). For the Atlantic, the Ga data are from 37°N 75°W to 36°N 73°W (Orians and Bruland, 1988b), and the Al data are from Rhode Island, across the Gulf Stream, into the Sargasso Sea, then down toward the Caribbean (Measures et al, 1984, stations 0-1206). For Zr and FIf the western North Pacific data are from 38°N 146°E to 16°N 169°W, and in the eastern North Pacific from 50°N 145°W to 49°N 126°W (McKelvey and Orians, 1993 McKelvey, 1994).

SEM equipped with an energy-dispersive spectroscopy (EDS) provides image of the materials as well as chemical analysis. Bi et al. investigated the cross-sectional morphology of the Nafion/Si02-supported sulfated zirconia composite membrane and obtained the silicon and zirconium element distribution in the polymer matrix by SEM-EDS. ° Chalkova et al. carried out surface and cross-sectional morphology study of Nafion/Ti02 composite membranes by SEM-EDS. ... 

Brindley and Sempels (1), Vaughan et al. (2) and Shabtai (3) have shown that the experimental conditions of Al intercalation influences the physicochemical properties of the clay. The nature, amount and spacial distribution of the pillars change the thermal stability, texture and acidity of the pillared clays. For example, Rausch and Bale (4) have reported that the OH/Al ratio modifies the structure of the Al complex and that monomeric [Al(0H)x(H20)6-x] " or polymeric [A1i304(0H)24(H20)i2] species can be obtained. Clearfield (5) demonstrated that the polymerisation state of Zr species depends on the temperature, concentration and pH of the solutions. In any case, the height of pillars is largely controlled by the polymerisation state of the intercalated complexes. However, in order to maintain the accessibility of the inner surface, the density or spacial distribution of the pillars has to be controlled. This parameter has been studied by Flee et al (5), and Shabtai et al (7) for Al pillared clays and Farfan-Torres et al (8) for zirconium. 

Layers consisting of two components were realized by employing two targets. This is demonstrated in Figure 3.7 with the components zirconium and platinum on a stainless-steel substrate. Zirconium and platinum were evenly distributed within the layer. The surface roughness of the steel substrate was responsible for the steady incline of the iron concentration curve. 

According to SIMS data (not shown here for brevity), zirconium cations and fluorine anions are rather uniformly distributed across the particle depths, while calcium tends to segregate at the surface, where its content is up to several times higher than in the bulk. 

Zirconium is still designated, as far as the finest commercial grade is concerned, as JAN-Z-00399B with several exceptions. Grade 120A of the Foote Mineral Company and a comparative grade made by Ventron Corporation, Metal Hydrides Division are the ones to choose from. Both conform also to particle-size distributions and surface-area recommendations that came out of DOFL (now HDL) investigations. "... 

Another type of inorganic matrix that is similar to controlled-pore glass but considerably less expensive can be prepared by fusing inorganic compounds such as finely pulverized silica and zirconium oxide to form a porous body. Although the pore distribution is less imiform, the surface composition is almost imiform in the case of silica, the surface is nearly 100% silica. Controlled-pore... 

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