Scanning Tunneling Microscope
Mostrando 13-18 de 18 artigos, teses e dissertações.
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13. Imaging of single uncoated DNA molecules by scanning tunneling microscopy.
Scanning tunneling microscope images of DNA molecules absorbed onto highly oriented pyrolytic graphite have been obtained. Three methods of deposition and sample preparation have been utilized. In the first method, a highly concentrated solution of DNA is sonicated, and a drop is deposited on freshly cleaved graphite. Under these conditions, the molecules te
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14. Nanoscale imaging of chemical interactions: Fluorine on graphite
Using C60-functionalized scanning tunneling microscope tips, we have investigated the adsorption of fluorine on graphite. Based on characteristics of the accompanying electron standing waves, we are able to distinguish the fluorine adatoms that have bonded ionically to the graphite surface from those that have formed covalent bonds with the surface. This res
The National Academy of Sciences.
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15. High-resolution topography of the S-layer sheath of the archaebacterium Methanospirillum hungatei provided by scanning tunneling microscopy.
The inner and outer surfaces of the sheath of Methanospirillum hungatei GP1 have been imaged for the first time by using a bimorph scanning tunneling microscope (STM) on platinum-coated or uncoated specimens to a nominal resolution in height of ca. 0.4. nm. Unlike more usual types of microscopy (e.g., transmission electron microscopy), STM provided high-reso
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16. High-Resolution Scanning Tunneling Microscopy of Fully Hydrated Ripple-Phase Bilayers
A modified freeze-fracture replication technique for use with the scanning tunneling microscope (STM) has provided a quantitative, high-resolution description of the waveform and amplitude of rippled bilayers in the Pβ, phase of dimyristoylphosphatidylcholine (DMPC) in excess water. The ripples are uniaxial and asymmetrical, with a temperature-dependent amp
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17. Measurement of a linear free energy relationship one molecule at a time
A systematic study of the dehydrogenation of substituted thiophenols by controlled charge injection from the tip of a scanning tunneling microscope (STM) reveals a pronounced dependence of the reaction yield on the position and the chemical nature of the substituent. We evaluate the dehydrogenation rate of para-halo-substituted species within a linear free e
National Academy of Sciences.
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18. Revealing the hidden atom in graphite by low-temperature atomic force microscopy
Carbon, the backbone material of life on Earth, comes in three modifications: diamond, graphite, and fullerenes. Diamond develops tetrahedral sp3 bonds, forming a cubic crystal structure, whereas graphite and fullerenes are characterized by planar sp2 bonds. Polycrystalline graphite is the basis for many products of everyday life: pencils, lubricants, batter
National Academy of Sciences.