Resolution diffraction

Hell S W and Kroug M 1995 Ground-state-depletion fluorescence microscopy a concept for breaking the diffraction resolution limit Appl. Phys. B 60 495-7... 

Figure Bl.22.11. Near-field scanning optical microscopy fluorescence image of oxazine molecules dispersed on a PMMA film surface. Each protuberance in this three-dimensional plot corresponds to the detection of a single molecule, the different intensities of those features being due to different orientations of the molecules. Sub-diffraction resolution, in this case on the order of a fraction of a micron, can be achieved by the near-field scaiming arrangement. Spectroscopic characterization of each molecule is also possible. (Reprinted with pennission from [82]. Copyright 1996 American Chemical Society.)...

Hell, S. W. and Wichmann, J. (1994). Breaking the Diffraction Resolution Limit by Stimulated-Emission—Stimulated-Emission-Depletion Fluorescence Microscopy. Opt. Lett. 19, 780-2. 

It is emphasized that the final result is the structure map of the examined crystal rather than a pseudo structure map. This is because the difftaction intensities have been pushed towards the corresponding kinematical values during the calculation of partial structure factor in each cycle of the correction. In addition, in the final step, structure refinement by Fourier synthesis modifies the peak heights towards the true values to some extent. It is obvious that all the missing structure information due to the CTF zero transfer is mended after phase extension. The amplitudes are provided by the electron diffraction data, and the phases are derived from the phase extension. As a result, the resolution of the structure analysis by this method is determined by the electron diffraction resolution limit. 

An alternative approach to higher resolution nucleosome structure was to solve the complete NCP structure by increasing the diffracting resolution of... 

A crystal is made up of repeating units called unit cells. Each unit cell in the crystal has the same number of atoms or molecules arranged in a pattern that repeats regularly in three-dimensions (Fig. 4.6). It is the regularity or periodicity that makes a crystal diffract X-rays, while it is the content of the unit cell that gives a crystal its unique diffraction pattern. Furthermore, the degree to which all unit cells and their content have the same orientation in a crystal is directly proportional to its diffraction resolution. 

Klar, T. A., Jakobs, S., Dyba, M., Egner, A., and Hell, S. W. 2000. Fluorescence microscopy with diffraction resolution barrier broken by stimulated emission. Proc. Natl. Acad. Sci. USA 97 8206-10. 

Until the advent of superresolution microscopes the only way to observe the minute world was based on the common Fourier-type microscopes. The maximum theoretical resolution limit for these apparatuses was established by Abbe, applying the Rayleigh-Fourier diffraction resolution rule [28]. The basic principle underlying the operational working of these ordinary microscopes is, in the eyes of Niels Bohr, a textbook example of Heisenberg uncertainty relations. 

S.W. HeU, Improvement of lateral resolution in far-Held light microscopy using two-photon excitation with offset beams. Opt. Commun. 106, 19-24 (1994) S.W. HeU, J. Wichmann, Breaking the diffraction resolution limit by stimulated emission stimulated emission depletion fluorescence microscopy. Opt. Lett. 19(11), 780-782 (1994)... 

S.W. Hell, J. Wichmami, Breaking the diffraction resolution limit by stimulated emission stimulated-emission-depletion fluorescence microscopy. Opt. Lett. 19, 780-782 (1994)... 

A large number of proteins and other biomolecular crystals have been grown in space. The first Shuttle flight after the Challenger accident (STS-26) yielded crystals of 4 different proteins that were shown to have better diffraction resolution than the best crystals of these proteins that had ever been grown on Earth. This feat was even more remarkable, considering that the crystals produced in only a handful of space experiments were compared with the best crystals of these particular proteins that had been grown in... 

Not all space-grown biomolecular crystals were superior to those grown on Earth, but there were a number of cases of larger crystals, improved diffraction resolution, and lower mosasicity to merit a serious study among theorists to investigate how gravity... 

Method X-ray diffraction Resolution 2.00 Chains Asym./Biol. Unit A Keywords Heme peroxidase, peroxidase... 

Table 10.6 excluded from this count because the choice of enantiomeric related space groups is not made at the preliminary assessment stage of crystal quality and diffraction resolution. 

RT=diffraction resolution test RET=reduced exposure time LUC=large unit cell test ... 

In Figure 14.7, the energy resolution of proportional, scintillation, and semiconductor detectors is compared to wavelength-diffraction resolution. The energy resolution of the three types of detectors has approximately the same slope, that is, it is proportional to the square root of the photon energy. The resolving power of... 

When considering XRD data collection the photon energy also has to be taken into consideration. With higher energies the diffraction pattern is compressed and depending on the combination of the spatial resolution of the detector and the intrinsic beam size one could lose diffraction resolution. 

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