SEARCH · Search NASA
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Universal joint-type restraint that employs ball joints permits maximum angular and lateral offset movement in a bellows joint without danger of rupture or pressure drop in the line. It is used in high pressure and high temperature applications in refineries, steam plants, or stationary power plants.
Drill with modified cutting faces permits one-step drilling operation without chatter upon contact and premature wear. The modification of the drill, which has the same diameter as that of the desired hole, consists of a groove across the bottom of each of the cutting faces of the drill flutes.
Multisurface fixture with a tool holder permits accurate grinding and finishing of right and left hand single point threading tools. All angles are ground by changing the fixture position to rest at various references angles without removing the tool from the holder.
Hinge assembly permits flush mounting of doors and hatches of considerable thickness so that the axis of instant rotation, produced by the hinge, lies outside the panel surface and beyond the perimeter adjacent to the hinge. In operation, motion of the assembly is initially parallel, changing to angular after clearing the panel perimeter.
Dielectrometer permits measurement of dielectric constant and dielectric losses in a vacuum environment exposed to radiation. It is not necessary to remove the sample from the chamber during testing.
Known dc voltage is applied and then removed suddenly in a method to permit checkout of the mechanical and electrical condition of piezoelectric transducers of the cantilever beam type, while installed in a system.
Free floating support system in cryogenic pipe lines maintains the valve and valve operator in alignment. A Teflon sheet that is placed between the slide support plate and the base permits the valve and valve operator to move freely, as a unit, when the pipe line moves.
Franck-Condon factors for permitted transitions in nitrogen
Ultrasonic vibration of an assembly of stainless steel instrumentation tubes ensures brazing without flux. Vibration with an ultrasonic transducer permits the brazing material to flow down each tube in contact with a seal plug installed in a pressure vessel wall.
Failure Rate Index analysis permits comparison of reliability of alternate mechanical designs. All failure modes for a mechanical component are identified, and computed on an index which relates the failure mode to failure of the component. The summation of all failure mode indexes relates the potential reliability of the component.
Infrared image converter tube and a filtered light source monitor and measure the eye of a subject during experimental task-work operations to obtain a more natural measurement of unimpeded iris response. The device permits observation in the near infrared region, with little stimulation to the eye except by normal ambient lighting.
Modified directional filter is comprised of alternate pairs of dielectric and air gap filter sections with unequal electrical lengths. Filter provides more flexibility in choosing dielectric material thickness and permits switching from specially ground to standard thicknesses.
Reduction and analysis of electron content measurements permitting inference of electron density in solar wind
Pertinent documents are reported of the correspondance with the Department of Transportation for obtaining and revising Special Permit no. 6522 for the shipment of diborane. The documents reported cover the period from 4 June 1971 to 22 September 1972. The design and performance of 200-pound diborane shipping containers are included along with the requests for permission to ship quantities less that 200 pounds, and less than 100 pounds.
The ultraviolet oxygen emissions at 1304 and 1356 A in the tropical nightglow seen from Ogo 4 by Hicks and Chubb (1970) and Barth and Schaffner (1970) are accompanied by emission at 7774 and 4368 A, which have been studied from the ground by looking through the beam of an ionosonde operated under the Appleton anomaly ionization peaks. Simultaneous forbidden O I 6300-A measurements were also made. A theoretical value for the partial rate coefficient for 7774 emission by radiative recombination has been obtained, and from the ionospheric data and a model atmosphere the expected rates of radiative recombination and ion-ion recombination were calculated. The time variations and absolute intensity of the calculated and observed intensities agree reasonably well, when the uncertainties involved are considered. It is concluded that radiative recombination is the major source of the tropical oxygen permitted line emissions, accompanied by a small contribution from ion-ion recombination.
Using the Michigan multichannel spectrometer on the 1.3-meter telescope, relatively strong Fe II emission has been detected in the Seyfert galaxy NGC 7469. This object is different from the handful of others with permitted iron lines in that it also exhibits intense forbidden lines of oxygen. The observations do not show the strong He II at 4686 A reported by previous investigators.
Flexible metal seal permits rotation of object in vacuum chamber. Seal made from two cylindrical azimuthally fluted bellows attached to ends of cylindrical axially fluted bellows with connecting tubes at both ends. Designed for rotation of sample probes in electron spectroscopy for chemical analysis (ESCA), other applications likely.
Optical, X-ray and and/or IR spectra of Mrk 507, 5C 3.100 and I Zw 1 are compared in a discussion of the bases for classifications of Seyfert 1 and 2 galaxies. Einstein Observatory X ray data indicate that the Seyfert designation requires a continuum extending to X-rays in order to account for permitted Fe II lines observed in Seyfert galaxies. It is suggested that the IR luminosity of I Zw 1, which exceeds the X-ray luminosity by two orders of magnitude, may be accounted for by interaction between companion galaxies. The presence or absence of dense clouds such as those in I Zw 1 is identified as the factor which separates Seyfert galaxies into two mutually exclusive ranges in X-ray luminosity.