Transmission electron micrographs, pore

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. 

Fig. 17.2. (Opposite) Immuno-gold localization of a T. muris-derived IFN-y homologue to the bacillary band and cuticular pore. (A) Transmission electron micrograph of bacillary band showing the pore chamber (PC), pore aperture (PA) and lamellar apparatus (LA) (x22,000). (B) High-power localization of antibody staining (black dots) to the lamellar apparatus (LA) and pore chamber (PC) (x36,000). (Courtesy ofF. Bughdadi.)...

FIG. 3. Transmission electron micrograph of a microtomed section of a polycarbonate template membrane after deposition of An tubules within the pores of the membrane. Pore diameter was 50 mn. 

Figure 10.10 Transmission electron micrograph of ferritin entrapped in POPC liposomes (palmitoyloleoylphosphatidylcholine). Cryo-TEM micrographs of (a) ferritin-containing POPC liposomes prepared using the reverse-phase evaporation method, followed by a sizing down by extrusion through polycarbonate membranes with 100 nm pore diameters ([POPC] = 6.1 mM) and (b) the vesicle suspension obtained after addition of oleate to pre-formed POPC liposomes ([POPC] = 3 mM, [oleic acid - - oleate] = 3 mM). (Adapted from Berclaz et al, 2001a, b.)...

Figure 3.8 Schematic of the incorporation of metal nanoparticles in the pore walls of mesoporous silica using trialkoxysilane-functionalized nanoparticles (top). Transmission electron micrograph of a Pd nanoparticle incorporated in periodic mesoporous silica (bottom) [36].

Figure 5. Transmission electron micrograph of a mesoporous M41S-type silicate with pore sizes of 4 nm. The regular hexagonal arrangement of the pores can be seen in the micrograph and in the diffraction pattern shown in the inset.

Figure 2.15. Transmission electron micrographs showing the hexagonal structure of Pt him electrodeposited onto a polished gold electrode, (a) End view of the pores (b) side view of the pores. Reproduced with permission from [120],...

In the meantime it has also become feasible to sjmthesize other meso-porous materials that differ from CPG in that ttiey consist of individual, disconnected cylindrical pores. These so-called SBA-15 or MCM-41 silica pores can be synthesized using a technical-grade triblock copolymer as the structure directing template in aequous H2SO4 solution and tetraethyl orthosilicate as the silica source [33, 34]. After calcination [35], one obtains a regular array of individual cylindrical pores as illustrated by the transmission electron micrographs (TEMs) shown in Fig. 4.2. 

Figure 8.8 Plan-view transmission electron micrograph of columnar porous SiC with vertical pores of diameter 20 nm. Most of the SiC, except the top porous layer, was removed by polishing for this transmission image...

Figure 6. (a) Transmission electron micrograph of the ID arrangement of ligand-stabilized AU55 clusters in porous alumina. Because the diameters of the pore channel and cluster were 7 nm (approximately) and 4.2 nm, respectively, a helical structure was formed. 

Figure 8.1 An architectural model (left) and transmission electron micrograph (right) of an aerogel showing the nanostructured network and pore structure. (Left panel reproduced with permission from D. R. Rolison and B. Dunn, J. Mater. Chem. 2001, 11, 963. Copyright 2001 Royal Society of Chemistry. Right panel reproduced with permission from M. L. Anderson et al., Adv. Eng. Mater. 2000, 2, 481. Copyright 2000 Wiley-VCH.)...

Electron microscope inspection of a film replica of a polished surface of each of the bars as well as direct transmission electron micrographs of thin sections of each bar, reveals that these channels are evenly distributed throughout the bars. The channels are generally tetragonal or triangular in shape and have a diameter (calculated as the diameter of a circle having the same area as the pore cross section) of about 0.1-0.5 p.m. The pores are of such uniformity of size that practically no pores smaller than 0.1 pm or larger than 1 pm are found in the bars. The invention claimed is ... 

Fig. 10 Transmission electron micrograph of the microstructure resulting from selective anodic dissolution of Cu from a CusAu electrode (50 s anodic polarization at I = 1 mA cm in 1 M H2SO4). Black network is Au-rich Au j. jj), white spots are pores. (From Ref [52], with permission.)...

Estimates of the particle sizes obtained form the transmission electron micrographs indicated that the large-pore zeolite had an average particle size only about half that of the other zeolite.Since this corresponds to greater surface area per unit weight or volume, smaller particle size is presumably the origin of the better reinforcing ability of this zeolite. 

Fig. 1 Ultrastructure of a nucleus from chicken liver and diagrammatic representation of the nuclear envelope. (A) Transmission electron micrograph of an ultrathin section through a nucleus from baby chick (cockerel) liver, showing the perinuclear cytoplasm (Cyt), nuclear envelope (NE), nuclear pore complex (NPC), and nucleoplasm (Nu). Scale bar, 1 /im. (B) Diagram showing prominent features of the nuclear envelope—the lamina (L), inner nuclear membrane (INM), outer nuclear membrane (ONM), nuclear pore complex (NPC), rough endoplasmic reticulum (RER), and ribosomes (R).

Fig. 2 Transmission electron micrograph of karyoskeletal protein-enriched fraction prepared from Drosophila embryos. The main panel shows a nucleuslike structure, bounded by a peripheral lamina (L) Inset Higher magnification showing tangential section through the periphery of karyoskeletal protein structure as shown in the main panel. Nuclear pore complex remnants can be readily appreciated as small ringlike structures.

Fig. 10 Transmission electron micrograph of por-sPEEK-ZrP, pore diameter ca. 1-2 p.m. ZrP of thickness 30 nm coats the internal surfaces of the pores in an eggshell arrangement...

Fig. 2.2(b) Transmission electron micrographs of Bombyx mori sensilla trichodea (above, x 20 000 and 40 000) and s. basiconica (below, x 20 000). Fixation by freeze substitution results in almost round cross-sectional profiles of the dendrites, containing a regular array of microtubules. Pore tubules are well fixed in the outer parts of the hair (courtesy of Steinbrecht, 1980). 

Fig. 7. Transmission electron micrographs of several MCM-41 materials having pore sizes of 20,40,65,and 100 A (from [7])...

Figure III a and b show cross sectional transmission electron micrographs of the identical systems. The film ecimens were defined by focus ion beams (FIB) to genoate cross sectional thicknesses of (SO-100 nm). Areas containing pores appear lighter in color due to lower attenuation of the electron beam in those regions. The pores in these images are consistent in size to die values observed by SEM.

Fig. 5.29. Transmission electron micrograph of a stoma on stem of Opuntia ficus-indica. V, vacuoles m, mitochondria n, nucleus p, plastids po, stomatal pore (slightly open) sn, nucleus of a subsidiary cell (from Thomson and De Journett, 1970 a, by permission)...

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