Electron microscopy measurements

Figure 1.22 This surfactant orientation is supported by the 4-spacing values that were obtained from transmission electron microscopy measurements. In (A) the first suggested orientation the surfactant length is 2.4 nm and in (B) another orientation the surfactant length is 1.85 nm. (Reproduced from ref. 49, with permission.)... 

FIGURE 6.10 Experimentally measured diameter of submicron fused silica particles as a function of particles diameter determined from scanning electron microscopy measurements. Dashed line corresponds to 1 1 size relationship. (From Shcheslavskiy, V., Petrov, G. I., Faustov, A., Yakovlev, V. V., and Saltiel, 5. Optics Lett., 31(10) 1486-1488, 2006. Used with permission.)... 

Transmission electron microscopy measurements reveal that the nanotubes are selectively located in the PA-6 phase. The selectively filled PA-6/ABS blends show a highly irregular, cocontinuous morphology. 

It is necessary to note that the Langeven function L depends on variable D, over which the integration is conducted, Vg — %D3/6. Using this ratio and experimental dependence M(H), it is possible to get experimental size dispersion and then compare it with results of electron microscopy measurements. In the case when deviation of the granule shape from spherical is insignificant, such comparison testifies the applicability of the given model... 

Such techniques as XRD and electron microscopy measure the structure and/or chemical composition of catalysts extending below the surface where reaction occurs. The composition of the surface is usually different from that of the bulk, and thus its analysis must be carried out by techniques specific to the surface. It is on these surfaces that... 

The polystyrene latex (PSL) spheres were obtained from Seragen Diagnostics. The nominal sizes of these standards were from electron microscopy measurements. The samples were prepared by diluting the 10% solids in filtered, doubly distilled water, adding a small amount of SDS to help disperse the samples and sonicating with Branson 60 watt bath sonicator for 30 seconds to disperse any aggregates. The relative volumes (weights) of the two sizes of PSL in the mixed sample were estimated to be accurate to about 5-10%. 

Acknowledgement The authors are indebted to the German ministry BMBF (project 01GU0824) and the DFG (project SCHR621/2-3), for financial support, and to Dr. Walter Richter (Universitatsklinikum Jena) for performing the freeze-fracture electron microscopy measure-ments.The authors would like to thank Prof. Ulrich Seydel, former head of the Division of Biophysics, for continous support and development of new concepts in the biophysics of endotoxins. 

Characterisation of vesicles was achieved using a combination of methods, including photon-correlation spectroscopy, video-enhanced and cryo-electron microscopy. Measurements of the cmc of the surfactants (in the absence of salt) were made using uv-visible spectrophotometry and electrical conductivity (k). For cmc measurements, there is a convenient change in the extinction coefficient of the benzene chromophore at 262 nm. The onset of vesicle formation, and hence the determination of the esc, can be measured by 90° scattering and 180° optical turbidity measurements at 300 nm. 

Binary blends (50/50 wt%) of different combinations of the polymers of Table III were prepared from benzene solution as described above. Either electron microscopy, measurements of dynamic mechanical properties, or both were used to ascertain the heterogeneity (or homogeneity ) of each blend. 

Electron Microscopy Measuring structures of solids and surfaces down to the nanoscale using electrons rather than light. 

Figure 28 Schematic representation and operating principles of Li batteries, (a) Rechargeable Li-metal battery (the picture of the dendrite growth at the Li surface was obtained directly from in situ scanning electron microscopy measurements), (b) Rechargeable Li-ion battery. (Ref 47. Reproduced by permission of Nature Publishing Group (www.nature.com))...

The primary particle size of the powdered samples is to a certain extent of minor importance on the measured contact angle. The high pressure applied (10-1000 MPa) upon pelletizing causes the original particle size and shape to be distorted in such a way that a very smooth surface and a well-defined hole (advancing angle method) is obtained. This has been supported by Scanning Electron Microscopy measurements of the powders and pellets (see e.g. Fig. 3 for a Ni/AhOs catalyst). 

Transmission electron microscopy measurements revealed that the typical size of platinum particles in the calcined catalysts differ very much depending on the way the catalyst was prepared. The microemulsion catalysts exhibited similar and relatively small platinum particles with diameter (arithmetic mean) from 5 to 55 nm. In contrast with that, the 102 catalyst impregnated by classical method showed much larger Pt particles. An example of histograms of Pt particles observed in various catalysts is given in Fig. 4. The microemulsion catalysts have narrower particle size distribution located between 4-90 nm, while the catalysts impregnated by water solutions of chloroplatinic acid have much broader particle size distribution reaching diameters up to around 300 nm. 

The results that have been obtained with the catalysts after reduction and passivation are the same as those after calcination, i.e. the textural and structural properties of the support material have completely been retained after the treatments (as determined with nitrogen physisorption. X-ray diflfiaction and transmission electron microscopy). Information concerning the metallic nickel particles has been obtained with X-ray diffraction and transmission electron microscopy. Diflractograms of the catalysts after passivation are shown in Fig. 8. The observed features are exactly the same as for the oxidic systems (Fig. 4) only very broad and low diffractions are visible for the catalyst ex citrate, whereas sharp, intense peaks with a broad onset are observed for the catalyst ex nitrate. Consequently the nickel particles of the catalyst ex citrate have resisted sintering during the reduction treatment, thereby conserving the high dispersion of the catalyst. These results were confirmed by transmission electron microscopy measurements (not shown) only very small nickel nanoparticles situated inside the mesopores were found for the catalyst ex citrate. 

Through the use of simultaneous thermogravimetry modulated beam mass spectrometry, optical microscopy, hot-stage time-lapsed microscopy, and scanning electron microscopy measurements, the physical and chemical processes that control the thermal decomposition of RDX 9 below its melting point (160-189 °C) have been identified (Scheme 17) <2005PCA11236>. 

High catalytic activity is exhibited when one unit cell of NHCO is occupied by one (Pt)2 or (Pt)3 cluster. Hydrogen activation is caused by decomposition of H2 molecules to the atomic state with subsequent formation of the hydride complex. Oxidation-reduction titration as well as electron-microscopy measurements show the incorporation of Pd crystallites inside nylon grains [114]. Most have a mean diameter of about 30 A. However, under the assumption that all the metal is located on the polymeric support surface, the calculated accessible metal surface amounts to several hundred Angstroms. Therefore, during preparation of the Pd-nylon catalyst, part of the metal penetrates into the organic matrix. 

For the TEM analyses a drop of the suspension was placed on a carbon coated formvar support on a copper grid. Transmission electron microscopy measurements were made with a Philips EM301 electron microscope operating at 100 kV. 

Electron microscopy measurements on a very thin film of a styrene-isoprene block copolymer of 15,000 and 75,000 bloek molecular weights indicated that the polystyrene blocks form a spherical morphology with domains of 260 A diameter (Meier, 1969). Calculate the predicted domain size for this morphology (K = 0.670 A and assume a = 1.2). 

The diameter of these spheres is approximately 100 nm. This is in accordance with the previous theoretical calculations and transmission electron microscopy measurements. 

Figm 13 (a) Sequence and schematic representation of the self-assembly of an amphiphilic diblock elastin polypeptide into core-shell nanoparticles. Elastin-mimetic protein polymers that comprise fusions of elastin sequences with different 7, values can be induced to undergo self-assembly at a temperature between the two transition temperatures, (b) Differential scanning calorimetry measurements indicate an endothermic transition for the more hydrophobic (lower 7 block with a value that corresponds to those observed for the burial of hydro-phobic residues within a folded protein, (c) This transition coincides with the formation of spherical assemblies in which the more hydrophobic block is confined within the micellar core. Transmission electron microscopy measurements are consistent with spherical micelles and more complex assemblies. Reprinted from Lee, T. A. T. Cooper, A. Apkarian, R. P. Conticello, V. P. Adv. Mater. 2000, f2(15), Copyright 2000, with... 

Conformation and structure of A-block in solid state Infrared spectra of solid films of the samples cast from solution were measured with a Shimazu Modjl-30 A IR spectrophotometer in a region of 4000 to 400 cm. X-ray diagrams were obtained by using Ni-filtered Cu Ka radiation, setting a flat surface of the film parallel to a reflecting surface with an automatic diffractometer. For the electron microscopy measurement, thin films cast from solution were stained with osmium tetroxide and examined by transmission microscopy. 

Small angle A -ray spectroscopy is also widely" used, and Bassett et al. and others have used nitric-acid etching coupled with gel permeation chromatography to measure the distribution in stem lengths and effect of temperature and pressure on it. Electron microscopy measurements are also popular. ... 

Theoretical calculations, confirmed by electron microscopy measurement [53], revealed that homojunction dislocations in aluminum have either compact or... 

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