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G- , electron micrographs

Figure 5(g) Electron micrograph of inhibited styrene polymerized in a... [Pg.76]

Properties Rutile, specific surface area 174 m /g, electron micrograph available [2090]. Specific surcface area 48.8 m /g, average diameter 20 mn, spherical particles [359]. [Pg.481]

Properties Anatase, BET specific surface area 55 m /g, electron micrograph, XRD pattern available [2070]. [Pg.484]

Properties Anatase, specihc surface area 57 m /g, electron micrograph available [2090]. [Pg.491]

The surface area of crystalline bronzes is about 30 m g whereas the amoiphous sanqde reduced at S73 K (last line) exhibits a surface area of 20 m g. Electron micrographs of the bronzes Pt/HxMo03 show the presence of small Pt particles of 1 to 3 nm in diameter, homogeneously dispersed on the support. [Pg.684]

Gordon R., Bender R., Herman G.T. Algebraic reconstruction techniques (ART) for three-dimensional electron micrographs and X-ray photography., J. Theor. Biol., V. 29, 1970, p. 471-481. [Pg.220]

Fig, XIV-12. Freeze-fracture transmission electron micrographs of a bicontinuous microemulsion consisting of 37.2% n-octane, 55.8% water, and the surfactant pentaethy-lene glycol dodecyl ether. In both cases 1 cm 2000 A (for purposes of microscopy, a system producing relatively coarse structures has been chosen), [(a) Courtesy of P. K. Vinson, W. G. Miller, L. E. Scriven, and H. T. Davis—see Ref. 110 (b) courtesy of R. Strey—see Ref. 111.]... [Pg.518]

We have also examined the effect of stabilizer (i.e., polyacrylic acid) on the dispersion polymerization of styrene (20 ml) initiated with AIBN (0.14 g) in an isopropanol (180 ml)-water (20 ml) medium [93]. The polymerizations were carried out at 75 C for 24 h, with 150 rpm stirring rate by changing the stabilizer concentration between 0.5-2.0 g/dL (dispersion medium). The electron micrographs of the final particles and the variation of the monomer conversion with the polymerization time at different stabilizer concentrations are given in Fig. 12. The average particle size decreased and the polymerization rate increased by the increasing PAAc concentra-... [Pg.205]

Figure 12 The electron micrographs of the final particles and the variation of the monomer conversion with the time at different stabilizer concentrations in the dispersion polymerization of styrene. Stabilizer concentration (g/dL) (a) 0.5, (b) 1.0, (c) 2.0. The original SEM photographs were taken with 2600 x, 2000 x, and 2600 x magnifications for (a), (b), and (c), respectively, and reduced at a proper ratio to place the figure. (From Ref. 93. Reproduced with permission from John Wiley Sons, Inc.)... Figure 12 The electron micrographs of the final particles and the variation of the monomer conversion with the time at different stabilizer concentrations in the dispersion polymerization of styrene. Stabilizer concentration (g/dL) (a) 0.5, (b) 1.0, (c) 2.0. The original SEM photographs were taken with 2600 x, 2000 x, and 2600 x magnifications for (a), (b), and (c), respectively, and reduced at a proper ratio to place the figure. (From Ref. 93. Reproduced with permission from John Wiley Sons, Inc.)...
Figure 13-13. The glycogen molecule. A General structure. B Enlargement of structure at a branch point. The molecule is a sphere approximately 21 nm in diameter that can be visualized in electron micrographs. It has a molecular mass of 10 Da and consists of polysaccharide chains each containing about 13 glucose residues. The chains are either branched or unbranched and are arranged in 12 concentric layers (only four are shown in the figure). The branched chains (each has two branches) are found in the inner layers and the unbranched chains in the outer layer. (G, glycogenin, the primer molecule for glycogen synthesis.)... Figure 13-13. The glycogen molecule. A General structure. B Enlargement of structure at a branch point. The molecule is a sphere approximately 21 nm in diameter that can be visualized in electron micrographs. It has a molecular mass of 10 Da and consists of polysaccharide chains each containing about 13 glucose residues. The chains are either branched or unbranched and are arranged in 12 concentric layers (only four are shown in the figure). The branched chains (each has two branches) are found in the inner layers and the unbranched chains in the outer layer. (G, glycogenin, the primer molecule for glycogen synthesis.)...
Electron micrographs (scanning and transmission) showed that tungsten carbide is well dispersed on the surface of each support as nanosized particles (20 - 50 nm) as typified by the images in Figs. 3 (a b). However, BET surface area decreased in the order alumina > silica > titania > zirconia. With highest surface area obtained for each support being 240,133,18 and 9 m g respectively. [Pg.784]

Fig. 4a,b. Scanning electron micrographs of the crystalline products a in the presence of PAMA dendrimer (G=1.5) b in the absence of PAMA dendrhner (G=1.5) (reproduced from [28]... [Pg.148]

The macrostructure of the boron nitride obtained here is porous with pores 2 pm in diameter. There is no evidence for microporosity and the BET surface area 1s 35 m2 g-1. Transmission electron micrographs (Figure 4) show regions of well developed crystallinity. The crystalling grains are 5—10 nm on a side and 30-40 nm long. The BN (002) lattice fringes are clearly visible. [Pg.381]

Figure 4. Average end-to-end distance 1/2 versus contour distance L for xanthan from samples D ( V ), F ( ) and G ( ) calculated from electron micrographs obtained as described in Figure 1. was averaged over a total contour distance of 123 )im, 162 Jim, and 124 )im for samples D, F and G respectively. Figure 4. Average end-to-end distance <ra>1/2 versus contour distance L for xanthan from samples D ( V ), F ( ) and G ( ) calculated from electron micrographs obtained as described in Figure 1. <r2> was averaged over a total contour distance of 123 )im, 162 Jim, and 124 )im for samples D, F and G respectively.
Figure 7 (a, b, d, and e) shows transmission electron micrographs from Pd-Ag films of comparable weight, prepared and annealed at 400°C, and used once to catalyze the oxidation of ethylene at 240°C (40). The structure of this series of alloy films varied consistently with composition. Silver-rich films (e.g., Fig. 7a, 13% Pd) showed extensive coalescence of the crystallites, while at the other end of the composition range (e.g., Fig. 7e,... Figure 7 (a, b, d, and e) shows transmission electron micrographs from Pd-Ag films of comparable weight, prepared and annealed at 400°C, and used once to catalyze the oxidation of ethylene at 240°C (40). The structure of this series of alloy films varied consistently with composition. Silver-rich films (e.g., Fig. 7a, 13% Pd) showed extensive coalescence of the crystallites, while at the other end of the composition range (e.g., Fig. 7e,...
Fig. 2. Electron micrographs highlighting the polymorphism of amyloid fibrils. (A) A single human calcitonin protofibril with a diameter of 4 nm (adapted from Bauer et al., 1995). (B) Different morphologies present in a transthyretin fibril preparation. Black arrowheads show oligomers of different sizes, the black arrow points to a 9- to 10-nm-wide fibril, and the white arrowhead marks an 4-nm-wide fibril (adapted from Cardoso et al., 2002). (C-F) Human amylin fibril ribbons (adapted from Goldsbury et al., 1997). (C) A single 5-nm-wide protofibril. (D-F) Ribbons containing two (D), three (E), or five (F) 5-nm-wide protofibrils. (G) A twisted ribbon made of four 5-nm-wide protofibril subunits of Api-40 (adapted from Goldsbury et al., 2000b). Scale bar, 50 nm (A-G). Fig. 2. Electron micrographs highlighting the polymorphism of amyloid fibrils. (A) A single human calcitonin protofibril with a diameter of 4 nm (adapted from Bauer et al., 1995). (B) Different morphologies present in a transthyretin fibril preparation. Black arrowheads show oligomers of different sizes, the black arrow points to a 9- to 10-nm-wide fibril, and the white arrowhead marks an 4-nm-wide fibril (adapted from Cardoso et al., 2002). (C-F) Human amylin fibril ribbons (adapted from Goldsbury et al., 1997). (C) A single 5-nm-wide protofibril. (D-F) Ribbons containing two (D), three (E), or five (F) 5-nm-wide protofibrils. (G) A twisted ribbon made of four 5-nm-wide protofibril subunits of Api-40 (adapted from Goldsbury et al., 2000b). Scale bar, 50 nm (A-G).
Figure 3. Transmission electron micrographs of mesophyll cells of dormant cotyledons of A, Cucurbita foetidissima B, Cucurbita pepo C, Cucurbita palmata D, Cucurbita digitata E, Apodanthera undulata" Note cell wall (W), protein body (P), spherosome (S), globoid (G), and crystalloid (X). In each micrograph, the bar represents five microns. Reproduced from reference 14. Figure 3. Transmission electron micrographs of mesophyll cells of dormant cotyledons of A, Cucurbita foetidissima B, Cucurbita pepo C, Cucurbita palmata D, Cucurbita digitata E, Apodanthera undulata" Note cell wall (W), protein body (P), spherosome (S), globoid (G), and crystalloid (X). In each micrograph, the bar represents five microns. Reproduced from reference 14.
In addition, however, one can speculate about another possible application of stabilized vesicles in living systems tumor cells usually are not attacked by cells of the immune system. On the other hand it is impressive to see what happens if they are not able to elude the cells of the immune system. Antigens of cancer cells can be recognized e.g. by sensitized mice lymphocytes and the result is a destruction of the membrane of the malignant cell as demonstrated via electron micrographs by Old (12). [Pg.226]

As one may expect from the diversity of microorganisms that can reduce iron, the spectrum ranges from bacteria that can use only amorphous Fe(III) hydroxide/oxide (e.g., T. ferrireducens) and apparently require direct contact with the Fe(III) precipitate, as shown by electron micrographs (Slobodkin et al. 1997b), to bacteria that can utilize various forms of Fe(III) ion as precipitated hydroxide or as complexed soluble ions, such as Fe(III) citrate, to bacteria such as T. saccharolyticum that can use only soluble Fe(III) citrate but are stimulated by the addition of increased Fe(III) ions. Further studies must to be done to elucidate the nature and which of the bacteria excrete electron mediators (so no direct contact would be required) and which contain cell-wall-bound reductases (which require a direct contact with the Fe(III) precipitate). [Pg.247]

Some typical transmission electron micrographs of these polystyrene lattices are shown (Sample 2 and Sample 3) in Figure 10.6. The effects ofthe amount of stabilizer S is the relative amount of stabilizer) on the particle size is strong the more stabilizer applied, the smaller the particles are. It must be emphasized that this effective stabilization of nanopowders by our fluorinated block copolymers is not restricted to polymerization processes, but can be generalized to the fabrication of all organic nanopowders in media with low cohesion energy density, e.g., to the dispersion of dyes, explosives, or drugs. [Pg.159]


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Electron micrograph

Electron micrographs

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