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Fernandez-Moran, H.

Publications and source records attributed to Fernandez-Moran, H..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Investigations in space-related molecular biology

Improved instrumentation and preparation techniques for high resolution, high voltage cryo-electron microscopic and diffraction studies on terrestrial and extraterrestrial specimens are reported. Computer correlated ultrastructural and biochemical work on hydrated and dried cell membranes and related biological systems provided information on membrane organization, ice crystal formation and ordered water, RNA virus linked to cancer, lunar rock samples, and organometallic superconducting compounds. Apollo 11, 12, 14, and 15 specimens were analyzed

Fernandez-Moran, H.↗
NASA NTRS1973

High voltage electron microscopy of lunar samples

Lunar pyroxenes from Apollo 11, 12, 14, and 15 were investigated. The iron-rich and magnesium-rich pyroxene specimens were crushed to a grain size of ca. 50 microns and studied by a combination of X-ray and electron diffraction, electron microscopy, 57 Fe Mossbauer spectroscopy and X-ray crystallography techniques. Highly ordered, uniform electron-dense bands, corresponding to exsolution lamellae, with average widths of ca. 230A to 1000A dependent on the source specimen were observed. These were?qr separated by wider, less-dense interband spacings with average widths of ca. 330A to 3100A. In heating experiments, splitting of the dense bands into finer structures, leading finally to obliteration of the exsolution lamellae was recorded. The extensive exsolution is evidence for significantly slower cooling rates, or possibly annealing, at temperatures in the subsolidus range, adding evidence that annealing of rock from the surface of the moon took place at ca. 600 C. Correlation of the band structure with magnetic ordering at low temperatures and iron clustering within the bands was studied.

Fernandez-Moran, H.↗
NASA NTRS1973

Applications of cryogenics in electron microscopy

Description of research and development efforts which resulted in a high-voltage cryoelectron microscope system capable of consistent operation at 1.8 to 4.2 K. Attention is given to the design and operation of superconducting objective lenses providing enhanced resolution during longer exposure times at lower beam intensities (thus reducing radiation damage of specimens). A specific system described combines a closed-cycle superfluid helium refrigerator integrated with a modified 200 kV electron microscope. Consistent resolutions of 8 to 16 A are attained with significantly reduced radiation damage, contamination, and thermal noise in prolonged vibration-free examination of specimens at temperatures from 1.8 to 4.2 K. Applications in specific disciplines are discussed, including membrane ultrastructure, cryobiology, microelectronics, and general superconductivity research.

Fernandez-Moran, H.↗
NASA NTRS1972

Electron microscopy - A glimpse into the future.

A forecast attempt is presented on future advances in electron microscopic studies of membrane systems. A review of recent advances and present trends is followed by a discussion of prerequisites to further progress. Special attention is given to research areas of particular promise.

Fernandez-Moran, H.↗
NASA NTRS1971

Electron microscopy and diffraction of layered, superconducting intercalation complexes.

Several layered, transition metal dichalcogenide intercalation complexes with unique superconducting properties have been examined by high-resolution electron microscopy and electron diffraction. Details of the crystalline lattice and of the lattice imperfections have been directly resolved. The results can be correlated with the available X-ray diffraction and chemical data, and they confirm and extend the postulated models.

Fernandez-Moran, H.↗
NASA NTRS1970

Cell fine structure and function - Past and present

Electron microscopic studies of nerve membrane fine structure, discussing cell membrane multienzyme and macromolecular energy and information transduction, protein synthesis and nucleic acids interrelations

Fernandez-Moran, H.↗
NASA NTRS1969

High voltage electron microscopy and electron diffraction of pyroxenes in type B lunar samples from Apollo 11

Lunar pyroxene 10044 specimens cleaved and sectioned by diamond knife ultramicrotomy were examined by standard (75 to 100 kV) and high voltage (200 kV) electron microscopy and diffraction. Salient findings based on evaluation of 2000 plates show uniform 300 to 600 A-wide bands, probably corresponding to single crystal domains, with lattice spacings of 2. A High resolution bright and dark field images of iron-rich and magnesium-rich crystals were compared with corresponding electron diffraction patterns. Possible relations of observed structures to magnetic domains were considered.

Fernandez-Moran, H.↗
NASA NTRS1969

The world of inner space

Electron microscope application to research in biological evolution and molecular structure

Fernandez-Moran, H.↗