Microscope resolution

J. Perlo, F. Casanova, B. Bliimich 2005, (Profiles with microscopic resolution by single-sided NMR), J. Magn. Reson. 176, 64-70. 

In summary, we have commented briefly on the microscopic applications of NMR velocity imaging in complex polymer flows in complex geometries, where these applications have been termed Rheo-NMR [23]. As some of these complex geometries can be easily established in small scales, NMR velocimetry and visc-ometry at microscopic resolution can provide an effective means to image the entire Eulerian velocity field experimentally and to measure extensional properties in elastic liquids non-invasively. 

In all films there is a distribution of crystallite diameters. An example is shown in Fig. 2 for the film with a specific weight of 0.12 fig cm-2. The smallest particles whose diameters can be measured in a micrograph (and then only very approximately) have diameters of about 10 A, and this is the lower size limit used in Fig. 2. However, particles smaller than this can readily be observed in the micrograph, and there is no doubt that this type of film contains some crystallites down to the limit of microscopic resolution (about 8 A in our case), and presumably beyond. However, their number appears to be relatively small. It is interesting to compare the specific film weight of these ultrathin platinum films with the amount of platinum per unit actual surface area of support for typical supported platinum catalysts. A typical supported catalyst would have 1% (w/w) of platinum on a... 

The sensitivity of Z contrast for the detection of small clusters depends not only on the signal Z dependence, but also depends on the microscope resolution, which is governed by the probe size 6. A small cluster containing N atoms of atomic number Zi, supported on a film of effective atomic number Z2 of thickness t, will have a contrast in the annular detector signal given by... 

The surface of a crystal often shows irregularities such as steps, Idnks and holes. As microscopic resolution increases, smaller and smaller irregularities become visible. If similar surface morphologies are observed on all scales, regardless of magnification, these surfaces are termed self similar or self affine. 

Tsukahara, Y., Ohira, K Saito, M and Briggs, G. A. D. (1989b). Evaluation of polymer coatings by ultrasonic spectroscopy. In Acoustical imaging, Vol. 17 (ed. H. Shimizu, N. Chubachi, and J. Kushibiki), pp. 257-64. Plenum Press, New York. [214] Tsukahara, Y., Ohira, K., and Nakaso, N. (1990). An ultrasonic micro-spectrometer for the evaluation of elastic properties with microscopic resolution. IEEE 1990 Ultrasonics Symposium, pp. 925-30 [149]... 

Pope et al. (1991) applied chemical-shift-selective imaging at microscopic resolution of various plant materials, including dried and undried fruits of fennel, to the study of selective imaging of aromatics and carbohydrates, water and oil. The non-invasive nature of the method gives it advantages over established methods of plant histochemistry, which involve sectioning and staining to reveal different chemical constituents. 

At electron microscopic resolution, the striations appear more complex (Figure 6.2b). They correspond to densely and regularly packed filaments of actin and myosin, each composed of numerous, linearly pol5mierized subunits. The finer striations visible in EM are due in part to additional structural proteins, and in part to zones of overlap between actin and myosin. 

Synge, E. H. (1928). A suggested method for extending the microscopic resolution into the ultramicroscopic region. Philos. Mag. 6 356-362. 

Near-field scanning optical microscopy (NSOM) has been developed as a combination of scanning probe microscope and optical microscope in which the spatial resolution is determined by scanning probe microscope resolution while the signals detected are coming from several optical interactions. As a result, NSOM has achieved a higher spatial resolution than that of the classical optical microscopy that uses a conventional lens, which is strictly limited by the diffraction... 

M. Born, E. Wolf, Principles of Optics. 7th edn. (Cambridge University Press, Cambridge, New York, Melbourne, Madrid, Cape Town, 2002), p. 952 E.H. Synge, A suggested method for extending microscopic resolution into the ultra-microscopic region. Philos. Mag. 6, 356 (1928)... 

It is important that one be aware of the microscope resolution because if the particles are smaller than the optical resolution limit, the particles will appear to be blurry and it may affect the particle size analysis as a number of smaller particles may look tike a single larger particle. This artifact will result in overestimation of the size distribution. 

The straightforward approach to this kind of difficulty is to follow the time evolution of the system, for instance by molecular dynamics simulation, and wait until a sufficient number of events have been observed. However, the computational requirements of such a procedure are excessive for most interesting systems. In practice, it is frequently impossible to observe a single transition of interest, let alone collect enough statistics for a microscopic resolution of the mechanism. For instance, reaction times of chemical reactions occurring in solution often exceed the second time scale. Since the simulation of molecular systems typically proceeds in steps of roughly one femtosecond, of the order of 10 steps are required to observe just one transition. Such calculations are far beyond the reach of the fastest computers even in the foreseeable future. 

The rate of interface advance during nucleus growth is constant for most soild state decompositions for which measurements have been made. The rates of growth for the two nuclei shown here are equal. It is inferred, by extrapolation, that these were formed at times and but, as implied by the dotted lines, growth may have been slower during the very early stages (at or below the limits of microscopic resolution). 

Magnetic resonance imaging (MRI) is finding increasing application in areas that require microscopic resolution. While typical resolutions employed clinically are on the order of a millimeter, the notion of using MRI at microscopic resolutions arose... 

The dynamic sorption apparatus clearly demonstrates the advantages of performing dynamic rather than static measurements of spreading and penetration at microscopic resolutions on substrates as complex as paper. The ability to observe ink or toner/paper interactions in situ should be especially valuable for investigating other non-impact technologies. 

Synge E H 1928 Extending microscopic resolution into the ultra-microscopic region Phil. Mag. 6 356... 

A method that combines microscopic resolution and high-resolution lifetime measurement has been developed. This powerful technique allows detailed study of the location and environment of fluorescent labels in cells and other microscopic studies. It is expected that two-dimensional imaging will find a number of interesting applications in the near future. 

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