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At least 1,117 records · Page 62
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Technology transfer - The NASA perspective

Domestic and international NASA technology utilization experiences are described together with prospects for applying technology to problems of local and state governments. Transfer mechanisms used by NASA to introduce new technology in both the private and public sectors of the domestic scene are discussed, and attention is given to experiences gained in a pilot program designed to establish a refined methodology for the transfer of aerospace-developed technology to developing nations. Technical assistance to local and state governments involves applications of NASA experiences to further the constructive involvement of industry.

Carlson, J. M.↗
NASA NTRS1974

Is the zodiacal light intensity steady

It is pointed out that conclusions reported by Sparrow and Ney (1972, 1973) could be confirmed in an investigation involving the refinement of OSO-5 data on zodiacal light. It had been found by Sparrow and Ney that the absolute value of both the surface brightness and polarization of the zodiacal cloud varied by less than 10% over the 4-yr period from January 1969 to January 1973.

Burnett, G. B.↗
NASA NTRS1974

The experimental clean combustor program - Description and status

The experimental clean combustor program is a contract effort with primary objectives including the generation and demonstration of technology for development of advanced commercial CTOL aircraft engines with lower exhaust emissions than current aircraft, and the demonstration of this technology in full scale engines in 1976. The program is being conducted in three phases. These consist of screening of low pollutant combustors, refinement of the best combustors, and engine demonstration of the best combustors. Pollution goals are emission index values of 20 and 4 for carbon monoxide and unburned hydrocarbons respectively at engine idle conditions, and an oxides of nitrogen emission index level of 10 at engine takeoff conditions. Pollution reduction approaches which are being investigated include multiple burning zone combustors, investigations of improved fuel distribution, and preparation and the staging of combustor airflow.

Niedzwiecki, R. W.↗
NASA NTRS1974

Advances in the analysis and design of adhesive-bonded joints in composite aerospace structures

Several aspects of adhesive-bonded joint analysis and design are presented from the reference of size of structure or load intensity. This integrates the individual characterizations of double-lap, single-lap, stepped-lap, tapered-lap and scarf joints. The paper includes an overview of bonded joint selection from the standpoints of design, fabrication, and processing, each bearing in mind the influence of such considerations on the strength of the joint. A case study is presented of the optimization of a specific relatively thick titanium-to-graphite epoxy stepped-lap joint, using the digital computer analysis program A4EG. The factors accounted for are adhesive plasticity, adherend stiffness imbalance, adherend thermal mismatch, and change of material properties within the range of temperature environment and with load direction. The strength increases obtainable by refining the initial design are demonstrated.

Hart-Smith, L. J.↗
NASA NTRS1974

Observations of Circinus X-1 from Uhuru

Analysis of Uhuru observations of the X-ray source Cir X-1 (3U 1516-56) suggests that the source may be a binary with a period longer than 15.0 days. Significant intensity variations have been observed on all time scales from 0.1 sec to days. Changes in the X-ray energy spectrum from 2 to 20 keV have also been found. A refined X-ray position, containing no obvious optical counterpart, is reported. The similarities between Cyg X-1 and Cir X-1 suggest that the X rays from Cir X-1 may be produced by accretion onto a massive, collapsed object.

Jones, C.↗
NASA NTRS1974

Detection of dilute organic acids in water by inelastic tunneling spectroscopy

Study of inelastic electron tunneling spectroscopy (IETS) spectra obtained from junctions exposed to dilute solutions of organic molecules in both liquid and vapor phases. The results indicate that it is possible in principle to detect the presence and to measure the concentration of at least some organic molecules in dilute aqueous solution by means of the IETS technique. Some fine points pertaining to the application of this technique are discussed, and it is pointed out that through appropriate refinements IETS may become a valuable tool for analytical water chemistry.

Skarlatos, Y.↗
NASA NTRS1974

The repulsive 1 Sigma g/+/ He2 potential obtained from total cross sections

An improved apparatus for obtaining short-range molecular potentials is described. The setup is a refined version of that used by Jordan-Amdur and by Leonas. The ion source is provided with a mass analyzing magnet, the capacitance manometer in the scattering cell is calibrated with a McCleod gauge, and the detection unit substitutes a Channeltron multiplier for the thermopile. The measured ground-state He-He potential for radii between 0.49 and 1.56 A is approximately V(r) = 215 x exp(-3.95r) eV, which is 25% higher than the earlier experiments. The result is supported by molecular orbital and statistical model calculations.

Foreman, P. B.↗
NASA NTRS1974

The two-dimensional tunnel structures of K3Sb5O14 and K2Sb4O11

The structures of K3Sb5O14 and K2Sb4O11 have been solved by the single-crystal X-ray direct method and the heavy-atom method, respectively. The structure of K3Sb5O14 is orthorhombic, with space group Pbam and cell parameters a = 24.247 (4), b = 7.157 (2), c = 7.334 (2) A, Z = 4. The structure of K2Sb4O11 is monoclinic, with space group C2/m and cell parameters a = 19.473 (4), b = 7.542 (1), c = 7.198 (1) A, beta = 94.82 (2) deg, Z = 4. A full-matrix least-squares refinement gave R = 0.072 and R = 0.067, respectively. In both structures, oxygen atoms form an octahedron around each Sb atom and an irregular polyhedron around each K atom. By sharing corners and edges, the octahedra form a skeleton network having intersecting b-axis and c-axis tunnels. The K(+) ions, which have more than ten oxygen near neighbors, are located in these tunnels. Evidence for K(+)-ion transport within and between tunnels comes from ion exchange of the alkali ions in molten salts and anisotropic temperature factors that are anomalously large in the direction of the tunnels.

Hong, H. Y.-P.↗
NASA NTRS1975

Design criteria monograph on turbopump gears

Turbopump power gears were brought to acceptable levels of usefulness and reliability through refinements in interdependent areas of design, materials, processing, and quality control combined with extensive development testing that explored problem areas and evaluated potential solutions.

Source record↗
NASA NTRS1975

Improved axisymmetric potential flow computer program

Basic method of calculating potential flow has been refined to increase accuracy of results and to reduce computational time. Program calculates low speed flows about or within bodies of axially symmetric shape. Solid body, inlet, and purely internal flow problems can be solved.

Hess, J. L.↗
NASA NTRS1974

Physical forces influencing Skylab experiments M551, M552, and M553

The forces concerned with metals melting, exothermic brazing, and sphere forming experiments on Skylab 1 mission are reported. The conclusions reached are that no significant practical differences exist between terrestrial and microgravity electron beam melting, and braze gap clearances are far less critical to joining operations in space than on earth. Altered microstructures, increased grain refinement, and the appearance of a single, large interior shrinkage pore were found in the Skylab specimens.

Bourgeois, S. V.↗
NASA NTRS1974

Retention and application of Skylab experiences to future programs

The problems encountered and special techniques and procedures developed on the Skylab program are described along with the experiences and practical benefits obtained for dissemination and use on future programs. Three major topics are discussed: electrical problems, mechanical problems, and special techniques. Special techniques and procedures are identified that were either developed or refined during the Skylab program. These techniques and procedures came from all manufacturing and test phases of the Skylab program and include both flight and GSE items from component level to sophisticated spaceflight systems.

Gillespie, V. G.↗
NASA NTRS1975

Phase 2, 3 and 4 8 psi pressure glove

The feasibility of providing a high pressure, very mobile and reliable space suit glove system is demonstrated. A 'soft' toroidal wrist joint assembly was developed. A representative Kevlar and steel wrist section was tested and proved the useful lifetime to be in excess of 1,000,000 cycles. Improved comfort was accomplished by increasing the first finger metacarpal dimensions. Recommendations concern design refinements, and EVA configuration.

Elkins, W.↗
NASA NTRS1975

Better vacuum by removal of diffusion-pump-oil contaminants

The complex problem of why large space simulation chambers do not realize true ultimate vacuum was investigated. Some contaminating factors affecting diffusion pump performance were identified, and some advances in vacuum distillation-fractionation technology were achieved which resulted in a two-decade-or-more lower ultimate pressure. Data are presented to show the overall or individual contaminating effects of commonly used phthalate ester plasticizers of 390 to 530 molecular weight on diffusion pump performance. Methods for removing contaminants from diffusion pump silicone oil during operation and for reclaiming contaminated oil by high-vacuum molecular distillation are described. Conceptual self-cleansing designs and operating procedures are proposed for modifying large diffusion pumps into high-efficiency distillation devices. The potential exists for application of these technological advancements to other disciplines, such as medicine, biomedical materials, metallurgy, refining, and chemical (diffusion-enrichment) processing.

Buggele, A. E.↗
NASA NTRS1973

Handling properties of diverse automobiles and correlation with full scale response data

Driver/vehicle response and performance of a variety of vehicles in the presence of aerodynamic disturbances are discussed. Steering control is emphasized. The vehicles include full size station wagon, sedan, compact sedan, van, pickup truck/camper, and wagon towing trailer. Driver/vehicle analyses are used to estimate response and performance. These estimates are correlated with full scale data with test drivers and the results are used to refine the driver/vehicle models, control structure, and loop closure criteria. The analyses and data indicate that the driver adjusts his steering control properties (when he can) to achieve roughly the same level of performance despite vehicle variations. For the more disturbance susceptible vehicles, such as the van, the driver tightens up his control. Other vehicles have handling dynamics which cause him to loosen his control response, even though performance degrades.

Hoh, R. H.↗
NASA NTRS1975

Design and test of a pump failure anticipator

Tests were conducted on two different types of pumps in order to refine the concept and to finalize design details of a positive displacement internal gear pump and a shroudless centrifugal pump. A concept and a system that could be used with pumps to allow a rapid judgement to be made of the suitability of the pump for futher service is developed. Test results and detailed data analysis are included.

Frarey, J. L.↗
NASA NTRS1974

Effective use of ERTS multisensor data in the Northern Great Plains

The author has identified the following significant results. ERTS imagery was used as a tool in the identification and refinement of soil association areas; to classify land use patterns between crop and fallow fields; to identify corn, soybeans, and oats; and to identify broad generalized range ecosystems. Various data handling techniques were developed and applied to accomplish these tasks. A map outlining soil associations and relative land values was completed on a base mosaic of ERTS imagery and is included as an appendix to the report.

Myers, V. I.↗
NASA NTRS1975

Aluminum under high pressure: 1 equation of state

A curve of applied pressure P versus lattice constant a is calculated for single crystal aluminum. It results from an application of the method of structural expansions for deriving the energies of simple metals, a method known to give reasonable results for the elastic constants even at second order in the effective electron-ion interaction. The method is taken from Fermi surface analysis . This essentially experimental information is used to verify that the extant face-centered cubic structure remains the preferred crystalline phase up to the highest pressures considered. Arguments are given to suggest that the P versus a curve should have reasonable a priori accuracy, which may be improved if experimental data in the intermediate pressure region can be provided to refine the energy dependent pseudo-potential. At 3 megabars the lattice constant is reduced by only 22%; the ion cores at this pressure are still very well separated.

Friedli, C.↗