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Neutral and ion spectrometer to determine composition and distribution of contaminating gases from Apollo Telescope Mount
Amino acid composition and terminal sequences of ferredoxins from photosynthetic green bacteria
Carbon in austenite derived for composition dependence of diffusivity using first order mixing statistics
Development and fabrication of filament composite nondestructive test standards
Material fatigue failure under narrow band random vibration effects, deriving fatigue life prediction equation based on composite experimental design and statistical tests
The author has identified the following significant results. The main objective is to determine the extent to which can be used to differentiate between mine dumps having varying degrees of vegetative cover. At this stage it is clear that the various mine dumps can be located and identified. Differences in vegetative cover can be seen and measured. Patterns of vegetative growth, some characteristic to particular dumps, can also be seen. It is therefore tentatively concluded that mine dumps can be differentiated with respect to their vegetative cover on the imagery received to date, and this is reported as a significant result. Subsequent imagery showing seasonal variations should facilitate this program. In addition to work on the mine dumps, a photogeological project has been initiated on geotectonics of South Africa. Studies of ERTS-1 images has indicated that major structures (faults, folds, and linear features) associated with the three geotectonic environments can be identified. In addition, major as well as relatively minor stratigraphic subdivisions can be recognized by their color tones. Results obtained warrant continuation of this study using color composite prints enlarged to a scale of 1:500,000.
Eight chemical groups can be recognized on the basis of studies of more than 200 Apollo 14 glass particles of impact origin. It is found that the major rock type of a highland site is dominated by annealed noritic rocks rather than by anorthosites as previously suggested. Both mafic and salic rock types are associated with the noritic rocks. A number of tables are provided showing the chemical composition of the minerals investigated.
Discussion of the abundances relative to carbon of the elements from silicon to nickel in the galactic cosmic radiation as measured by cosmic ray telescopes on the IMP-5 and IMP-7 satellites, in energy ranges between 40 and 450 MeV/nucleon depending on the species. The IMP-7 measurements are still to be considered only preliminary and do not yet fully exploit the resolution capabilities of that instrument. Calculations of the abundances to be expected in this charge range if the cosmic radiation traverses 6 g/sq cm of material after acceleration are presented, and the consequences which follow both for propagation models and for the chemical composition of the sources of the cosmic radiation are discussed.
The association of comets with star formation in clusters is elaborated. This hypothesis is also used to explain origin and evaluation of the Oort cloud, the composition of comets, and relationships between cometary and interstellar molecules.
The stability fields of various sulfide phases that form on Fe-Cr, Fe-Ni, Ni-Cr and Fe-Cr-Ni alloys were developed as a function of temperature and the partial pressure of sulfur. The calculated stability fields in the ternary system were displayed on plots of log P sub S sub 2 versus the conjugate extensive variable which provides a better framework for following the sulfidation of Fe-Cr-Ni alloys at high temperatures. Experimental and estimated thermodynamic data were used in developing the sulfur potential diagrams. Current models and correlations were employed to estimate the unknown thermodynamic behavior of solid solutions of sulfides and to supplement the incomplete phase diagram data of geophysical literature. These constructed stability field diagrams were in excellent agreement with the sulfide phases and compositions determined during a sulfidation experiment.
Composite materials are discussed with reference to their mechanical and physical properties, fatigue and fracture testing and analysis, nondestructive evaluation, fabrication, and commercial applications. Particular papers are presented on such topics as analysis of mechanical strength data from hybrid laminates of glass and graphite fibers, graphite-aluminum composites, the mechanical behavior of molybdenum-reinforced metal composites, and composite laminate application in magnetic fusion energy superconducting magnet systems.
Plastic and Large Deflection Analysis of Nonlinear Structures (PLANS) system is collection of five computer programs for finite-element static-plastic and large deflection analysis of variety of nonlinear structures. System considers bending and membrane stresses, general three-dimensional bodies, and laminated composites.
The large and diverse set of observational data collected in the high-altitude plumes of the May 18, May 25, and June 13, 1980 eruptions is organized and analyzed with a view to discerning the processes at work. The data serve to guide and constrain detailed model simulations of the volcanic clouds. For this purpose, use is made of a comprehensive one-dimensional model of stratospheric sulfate aerosols, sulfur precursor gases, and volcanic ash and dust. The model takes into account gas-phase and condensed-phase (heterogeneous) chemistry in the clouds, aerosol nucleation and growth, and cloud expansion. Computational results are presented for the time histories of the gaseous species concentrations, aerosol size distributions, and ash burdens of the eruption clouds. Also investigated are the long-term buildup of stratospheric aerosols in the Northern Hemisphere and the persistent effects of injected chlorine and water vapor on stratospheric ozone. It is concluded that SO2, water vapor, and ash were probably the most important substances injected into the stratosphere by the Mount St. Helens volcano, both with respect to their widespread effects on composition and their effect on climate.
The long-term durability of those advanced composite materials which are applicable to aircraft structures was discussed. The composite components of various military and commercial aircraft and helicopters were reviewed. Both ground exposure and flight service were assessed in terms of their impact upon composite structure durability. The ACEE Program is mentioned briefly.
The surficial geology of the Kasei Vallis - Lunae Planum region of Mars was investigated using the three color Viking Orbiter 1 data. Spatial resolution is 820m and Ls = 100 deg, a season of low atmospheric and and surface dustiness. This region was chosen for high quality color and thermal inertia data as well as for the diversity of volcanic plains and fluvial landform. The data was reformatted to Mercator projection and calibrated to normal reflectance using in flight calibration parameters and observed photometric properties. Color properties from this image are displayed in two forms: the Red Albedo vs. Violet Albedo two dimensional histogram, and representative 3 point spectra. Virtually the full range of regolith color properties known from prior research is represented, plus some new characteristics. Interpretations of the data are presented which address general composition and formation processes of channel and intracrater deposits.
Twelve near-infrared spectra were obtained at the Mauna Kea Observatory 2.2-m telescopy using the Planetary Geosciences Division indium antimonide spectrometer. These include spectra obtained for two fresh surfaces on the inner Rook ring, two fresh craters in the outer Rook Mts., and two inner Rook ring, two fresh craters in the outer Rook Mts., and two fresh 11-km. craters (Eichstadt G and H) which are located between the outer Rook ring and the Cordillera ring and exposed material from within the knobby facies of the Montes Rook Formation. In addition, spectra were collected for portions of the Maunder Formation. Special attention was paid to the spectra collected for six immature features within the Cordillers ring. Analyses of the 1-micron band positions and shapes as well as continuum slopes indicate that the spectra for craters in the knobby facies and in the outer Rook Mts., while differing in detail, exhibit many common spectral characteristics. These spectra represent relatively fresh highlands rocks dominated by abundant Fe-bearing plagioclase feldspar and Ca-poor orthopyroxene. Compositions ranging between noritic anorthosite and anorthositic norite are indicated.
The polyimide from BTDA 1,6-hexanediamine and m-phenylenediamine was selected from a prior study for the present study. Methods to prepare prepreg which would provide low void composites at low molding pressures from the thermoplastic polyimide were studied. Cresol solutions of the polyimide were applied to a balanced weave carbon fabric and the cresol removed prior to composite molding. Low void composites were prepared from smoothed prepregs at high pressures (34.5 MPa) and temperatures as low as 260 C. Lower molding pressures lead to higher void composites. Need for a lower melt viscosity in the neat resin is suggested as a requirement to achieve low void composites at low pressures. Some mechanical properties are included.
The results of a petrological and geochemical study of the dimict breccia 61015 at the Apollo 16 site are presented and discussed. The breccia consists predominantly of granulated anorthosite and impact melt rock of very high aluminum-basalt composition. It probably formed in the floor of an expanding crater cavity when impact melt generated within the cavity was injected into underlying anorthositic bedrock and solidified rapidly, the anorthosite and melt rock being fragmented by deformation in the later stages of the impact. A possible source crater for the breccia is identified. The breccia has been affected by at least one recent small impact, which produced internal shock-induced melting of the breccia and injected and coated the rock with externally derived melts. The TiO2 content of the coating and vein glasses establish that they cannot be melted soils; their composition requires a mafic, low-TiO2 protolith component.