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We introduce and demonstrate a new microscopy concept: imaging interferometric microscopy (IIM), which is related to holography, synthetic-aperture imaging, and off-axis-dark-field illumination techniques. IIM is a wavelength-division multiplex approach to image formation that combines multiple images covering different spatial-frequency regions to form a composite image with a resolution much greater than that permitted by the same optical system using conventional techniques. This new type of microscopy involves both off-axis coherent illumination and reinjection of appropriate zero-order reference beams. Images demonstrate high resolution, comparable with that of a high-numerical-aperture (NA) objective, while they retain the long working distance, the large depth of field, and the large field of view of a low-NA objective. A Fourier-optics model of IIM is in good agreement with the experiment.  相似文献   
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Selective and independent dimerization of tri- and tetraurea derivatives was used to build up dendritic assemblies which are uniform in size and structure. Dendrimers with the total molecular masses of about 25 000 g/mol were obtained. The existence of uniform assemblies was proved by 1H and 1H DOSY NMR experiments and also by dynamic light scattering.  相似文献   
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Tri-(2-alkoxy-5-ureido-phenyl)methanes represent a novel self-complementary motif forming hydrogen bonded homo- and heterodimers in nonpolar, aprotic solvents as evidenced by 1H NMR and ESI-mass spectra and by the formation of heterodimers. MD simulations suggest the formation of hydrogen bonds of different strength in agreement with NMR data. The dimerization does not interfere with that of tetraurea calix[4]arenes. A combination of both motifs may be used therefore to build up larger structures via self-assembly processes. [structure: see text]  相似文献   
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Abstract

The electrical charge assosiated with dislocation motion in KCl:Ba has been studied within the interval from 77 to 292K using on indentation method. The comparison of the potential difference values at 77 and 292K was performed on condition that the impression diagonals were roughly equal. The kinetics of the potential change was studied.  相似文献   
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Journal of Theoretical Probability - The present paper investigates the effects of tempering the power law kernel of the moving average representation of a fractional Brownian motion (fBm) on some...  相似文献   
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A convenient synthetic approach towards previously unknown N- and N,O-silylated α-iminophosphonates bearing fluoroalkyl groups at the imine C atom was developed. The synthetic potential of the compounds was demonstrated by their easy functionalization and the straightforward preparation of biorelevant aminophosphonates and free aminophosphonic acids with heterocyclic residues in the α-position.  相似文献   
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