PERMUTATIONS BY CUTTING AND SHUFFLING
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Cosmic ray deflections in geomagnetic field, variational coefficients, and diurnal intensity variations - tables
Technique uses a stiff medium in the annular space between inner and outer pipes of jacketed piping in transfer lines. The process eliminates splitting and welding and makes possible the use of standard pipe-bending tools.
Slip bands in elastic, isotropic, thin plates with rectilinear slits developed under simple tension
Relativistic solution by Landau procedure of initial value problem for one dimensional electron plasma wave coexisting with charged immobile background
Four samples were studied as part of the evaluation of the component parts of the material recovered from the Surveyor 3 spacecraft. Before analyzing the samples, a calibration sample was obtained. The distribution of lunar fines on painted and polished surfaces is presented.
Sco X-1 was observed on June 10, 1972 near 04 hr 33 min U.T. simultaneously in the optical (B) the soft X-ray (0.1 to 2.4 keV) and the X-ray (1.5 to 20 keV) bands of the spectrum. It is believed that a change of short duration in the absorbing medium associated with Sco X-1 was observed. The medium attenuating the low energy X-ray flux from Sco X-1 has apparently changed by more than 40% on a time scale of less than 45 sec.
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Technical memorandum describes design of linear reactor fabricated from grain-oriented steel. It includes design charts and nomographs and illustrates design of grain-oriented inductor via seven-step example. Typical values of core inductance, operating frequency, and coil current (dc and ac) are given.
Three lathe tools form different joints in gasket material.
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Soil features located with minimum time and labor. Ground-penetrating radar (GPR) system supplements manual and mechanical methods in performing subsurface soil survey. Mobile system obtains graphic profile of soil discontinuities and interfaces as function of depth. One or two test borings necessary to substantiate soil profile. GPR proves useful as reconnaissance tool.
A systematic wind-tunnel investigation has been performed on a series of spherically blunted 10-degree cones to determine Mach number and angle-of-attack effects on the hypersonic static stability. The cones, which range in nose-to-base radius ratios from 0 to 0.5, have been tested from -4 to 20 degrees angle of attack at Mach numbers of 6 and 10 in air and 20 in helium. Relatively large excursions in the center-of-pressure location were observed for small changes in cone nose bluntness. The movement of the center of pressure was also noted to become more pronounced as Mach number increased; increases in angle of attack tended to lessen the magnitude of these excursions. Computational predictions of basic aerodynamic coefficients as well as the center-of-pressure locations using both viscous and inviscid theory compare very well with the experimental data.
A ball-on-cylinder machine (BOCM) was used to measure the lubricity of fuels. The fuels tested were well-characterized fuels available from other programs at the NASA Lewis Research Center plus some in-house mildly hydroprocessed shale fuels from other programs included Jet-A, ERBS fuel, ERBS blends, and blend stock. The BOCM tests were made before and after clay treatment of some of these fuels with both humidified air and dry nitrogen as the preconditioning and cover gas. As expected, clay treatment always reduced fuel lubricity. Using nitrogen preconditioning and cover gas always resulted in a smaller wear scar diameter than when humidified air was used. Also observed was an indication of lower lubricity with lower boiling range fuels and lower aromatic fuels. Gas chromatographic analysis indicted changes in BOCM-stressed fuels.
A detailed analysis of the metal-carbonyl bonding in Ni(CO)4 and Fe(CO)5, based on the newly developed contained space orbital variation (CSOV) method, is carried out to investigate various contributing factors to the interaction. Three aspects about the metal-CO interaction are presented: (1) the frozen orbital repulsion between the metal 4s and the CO is large; (2) the metal to CO pi donation is energetically much more important than the CO to the metal sigma donation; and (3) the metal 4s and 4p orbitals make a very small contribution (smaller than 0.4 eV) to the interaction energy; the largest portion of this contribution arises from the CO to metal sigma donation.
Fatigue tests were conducted to determine the actual reduction in fatigue life due to weight removal for balancing by: hand grinding, low power (20 watt) Nd:glass laser, and high power (400 watt) Nd:YAG laser.
Fatigue lives made to approach those attainable by traditional grinding methods. Fatigue-test specimens prepared from four metallic alloys, and material removed from specimens by manual grinding, by Nd:glass laser, and by Nd:YAG laser. Results of fatigue tests of all specimens indicated reduction of fatigue strengths of laser-fired specimens. Laser machining holds promise for improved balancing of components of gas turbines.
The objective of this experiment is to provide a simple, inexpensive composite fabrication technique which can be easily performed with a minimum of equipment and facilities. This process eliminates expensive female molds and uses only male molds which are easily formed from foam blocks. Once the mold is shaped, it is covered with fiberglass and becomes a structural component of the product.