Average size nodules

Khayet et al. [31] studied the surfaces of asymmetric poly(etherimide) (PEI) ultrafiltration membranes by AFM. Membranes were prepared by casting mixtures of PEI, hydroxybutyric acid y-lactone (GBL, y-butyrolactone) as nonsolvent and N,N-dimethylacetamide (DMAc) at 50 °C. The average size of the nodule aggregates versus PEI concentration is given in Fig. 4.16. From Fig. 4.16, it is clear that the nodule aggregate diameter increases as the PEI concentration increases. 

Hepatic nodules are found in less than 5% of patients in most series (70,73) although frequencies as high as 53% (17/32) have been reported (71). The nodules are typically discrete and of low attenuation, requiring intravenous contrast to be visualized (Fig. 9) (70,71,74,75). They are always multiple and usually innumerable with an average size of 0.6 to 0.75 cm in diameter but may be as large 2.0 cm and tend to become confluent as they enlarge (70,71). Hepatic nodules are seen much less frequently than splenic nodules (70,71,76). The... 

Core-shell nanocomposite of Mg(OH)2/PMMA with an average particle size of ca. 500nm where Mg(OH)2 is the core and PMMA is the shell was successfidly prepared by the emulsion polymerization of MMA in the presence of surface modified Mj OH)2. The grapelike ( re-shell microspheres with PMMA nodules could he obtained as stable latex. 

Figure 30. Speciation of Ni and Zn in a ferromanganese nodule from the Morvan region, France (Baize and Chretien 1994 Latrille et al. 2001 Manceau et al. 2002b). a) Photomicrograph of a soil thin section (30 pm thick) containing embedded ferromanganese concretions, b) Average enrichment factor of elements in soil nodules. Adapted from Palumbo et al. (2001) and Childs (1975). c) pSXRF elemental maps recorded on beamline 7.3.3 at the ALS (Berkeley). Beam energy 10 keV, illuminated area 14 pm (H) x 11 pm (V), step size 20 x 20 pm, dwell time 3s/pt.

Five points-of-interest were selected for Zn -edge p.EXAFS measurements in such a manner as to vary the proportions of lithiophorite and Mn-feroxyhite on the basis of pXRD analysis (Fig. 32a). As a first approximation, the five spectra look like a linear combination of two end-members, with spectrum 1 collected in a lithiophorite-rich spot and spectrum 5 in a Mn-feroxyhite-rich spot. Figure 32b shows in dots a fluorescence-yield spectrum taken of a powdered pellet of ten nodules, on ESRF Beamline BM32 and with a beam size big enough to ensure that the spectrum represents an average over all nodules. We see that this spectrum does not seem to belong to the same pseudobinary series as the five micro-EXAFS spectra, a point to which we shall return below. 

Membrane Average nodule diameter, scan size 500 nm (nm) Mean roughness, Ra, scan size 1 Xm (run)... 

Khulbe et al. [4] also measured the nodule sizes (the average of at least 20 measurements) at the inner surface, at the areas near the inner surface, in the middle section and near the outer surface, and at the outer surface for hollow fibers fabricated at different air gaps. Table 6.1 summarizes the results. 

Table 6.1. Average nodule size at the inner and outer surfaces and in the cross section near the inner surface, middle section, and near the outer surface of UF poly(etherimide) hollow fibers for different air gaps...

On the floor of the ocean, at a depth of approximately 4000 m, so-caUed manganese nodules may be found (Figure M42). They are manganese and other metal oxides and clay. Nodules of economic interest contain 25-30% Mn, 1.5% Ni, 1.2% Cu, 0.3% Co and 0.05% Mo. The diameter of the nodules is on average 50 mm but the size varies... 

Figure 24 shows top surface at the size of 1 pm. It seems that a supemodular aggregate contains nodules with average diameter of 43.7 nm. Table 14 includes the data on the dependence of roughness parameters on the scan size with respect to the same PPO-CS2 membrane. 

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