9,320 research outputs found
Post-operative cranial pressure monitoring system
System for monitoring of fluidic pressures in cranial cavity uses a miniaturized pressure sensing transducer, combined with suitable amplification means, a meter with scale calibrated in terms of pressures between minus 100 and plus 900 millimeters of water, and a miniaturized chart recorder covering similar range of pressures
Studies of molecular properties of polymeric materials
Aerospace environment effects (high energy electrons, thermal cycling, atomic oxygen, and aircraft fluids) on polymeric and composite materials considered for structural use in spacecraft and advanced aircraft are examined. These materials include Mylar, Ultem, and Kapton. In addition to providing information on the behavior of the materials, attempts are made to relate the measurements to the molecular processes occurring in the material. A summary and overview of the technical aspects are given along with a list of the papers that resulted from the studies. The actual papers are included in the appendices and a glossary of technical terms and definitions is included in the front matter
Absorbed dose thresholds and absorbed dose rate limitations for studies of electron radiation effects on polyetherimides
The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit were studied. Total absorbed doses from 1 kGy to 100 MGy and absorbed dose rates from 0.01 MGy/hr to 100 MGy/hr were investigated, where 1 Gy equals 100 rads. Total doses less than 2.5 MGy did not significantly change the tensile properties of the film whereas doses higher than 2.5 MGy significantly reduced elongation-to-failure. There was no measurable effect of the dose rate on the tensile properties for accelerated electron exposures
Atomic beam source of polarized electrons
Polarized electrons produced by atomic beam apparatus - hyperfine structure intervals of alkali atom
Pennsylvania Folklife Vol. 39, No. 3
• The General Store • Pennsylvania German in Public Life • Building a One-Room School: The Dynamics of School Board Decision-Making at the Turn of the 20th Century • Washington Hood: 500th Graduate of the United States Military Academy • Grandmother Schultz • Aldes un Neies (Old and New)https://digitalcommons.ursinus.edu/pafolklifemag/1127/thumbnail.jp
AN IRRADIATION EXPERIMENT TO STUDY THE COMPATIBILITY OF BeO WITH GRAPHITE AT 1500C. PART II. OPERATION AND POSTIRRADIATION EVALUATION.
Birth Weights, Weaning Weights, and Average Daily Gain of Romosinuano-Sired Calves from First and Second Calving Angus X Brahman (F-1) Cows
Last updated: 6/12/200
Studies of molecular properties of polymeric materials: Aerospace environmental effects on three linear polymers
The development of crystal handling techniques for reflection infrared spectroscopy and methods for the fabrication and testing of tensile specimens are discussed. Data from mechanical, ac and dc electrical, and electron paramagnetic resonance studies conducted to determine the effects of 0.1-MeV and 1.0-MeV electron radiation on Mylar, Kapton, Ultem, and metal-doped Ultem are presented. Total doses ranging from 1 X 10 to the 8 rads to 1 X 10 to the 10 rads and dose rates from 5 X 10 to the 7 rads/hr to 1 X 10 to the 9 rads/hr were employed. The results of a study on the effects of aircraft service-environment fluids on Ultem are also reported. The weights and mechanical properties of Ultem were evaluated before and after exposure to water, JP4, Skydrol, an antifreeze, and a paint stripper
Recent results and new hardware developments for protein crystal growth in microactivity
Protein crystal growth experiments have been performed on 16 space shuttle missions since April, 1985. The initial experiments utilized vapor diffusion crystallization techniques similar to those used in laboratories for earth-based experiments. More recent experiments have utilized temperature induced crystallization as an alternative method for growing high quality protein crystals in microgravity. Results from both vapor diffusion and temperature induced crystallization experiments indicate that proteins grown in microgravity may be larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions than the best crystals of these proteins grown on earth
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Development of a recycle fuel for the HTGR
A Weak-Acid Resin-derived (WAR) kernel has been selected as the new reference recycle fuel, and the irradiation program reoriented toward establishing optimum specifications. The loaded resin is carbonized to a dispersion of UO in carbon at about 1200C. Continued heating to higher temperatures can convert the UO to carbide, completely at 1800C. Performance of WAR fuels at three levels of conversion is compared. 5 references (auth
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