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.
The present invention relates generally to polyimides. It relates particularly to novel polyimides prepared from 2,3, 3',4' -biphenyltetracarboxylic dianhydride and aromatic diamines. These novel polyimides have low color, good solubility, high thermal emissivity, low solar absorptivity and high tensile strength.
The effects of lattice distortion on the physical properties of La (sub 0.7)Ca(sub 0.3)MnO(sub 3) and La(sub 0.5)Ca(sub 0.5)CoO(sub 3) films are investigated. Our results suggest that larger substrate-induced lattice distortion gives rise to larger zero-field resistivity and larger negative magnetoresistance.
Experimental and theoretical collisional excitation cross sections are reported for the transitions 3s(sup 2)3p(sup 3) (sup 4)s(deg) (leads to)3s(sup 2)3p(sup 3)(sup 2)D(deg), (sup 2)p(deg) and 3s3p(sup 4) (sup 4)p in s//.
The spectroscopic constants and vibrational frequencies for the 1(sup 3)A' states of HNC, DNC, HOC+, and DOC+ are computed and discussed in this work. The reliable CcCR quartic force field based on high-level coupled cluster ab initio quantum chemical computations is exclusively utilized to provide the anharmonic potential. Then, second order vibrational perturbation theory and vibrational configuration interaction methods are employed to treat the nuclear Schroedinger equation. Second-order perturbation theory is also employed to provide spectroscopic data for all molecules examined. The relationship between these molecules and the corresponding 1(sup 3)A' HCN and HCO+ isomers is further developed here. These data are applicable to laboratory studies involving formation of HNC and HOC+ as well as astronomical observations of chemically active astrophysical environments.
While the HEEET project established the dual-layer, 3-D Woven TPS at TRL 6 for extreme entry environment missions such as Saturn and Ice-Giant Probe missions, subsequent to the completion of HEEET project in 2018, further development was undertaken to assess the viability of a variant of the 3-D Woven, a single, insulating layer alone as a viable TPS for Mars Sample Return mission. MSR Earth Entry System (EES) baselined it and named the TPS as 3D, mid-density, carbon-phenolic (3MDCP). MSR program invested in building a new loom and the weaver T.E.A.M. Inc is currently weaving 80” wide 1.2” thick insulating layer. Unlike HEEET, where a set of tiles and seams are integrated to form the heat-shield, 3MDCP is a seamless heatshield by wrapping and shaping a flat panel into the heatshield shape and then rigidizing the preform through resin infusion. MSR EES is investing in technology maturation of 3MDCP for the current mission launch in 2027. This lighting talk will provide key developments and time line for 3MDCP technology maturation to show that 3MDCP will be ready to support future UOP or Saturn Probe mission. In addition, the limitations of the capability will be presented so that Saturn mission proposers as well as UOP flagship mission study can be fully informed as to the 3MDCP capability.
Converts data from ORDEM 3 or MEM 3 files to STENVI format
Fast neutron spectrometer based on combination of solid state detectors and helium 3 filled proportional counters
Television pictures transmitted to earth from lunar surface by Surveyor 3
Intermediacy of azomethine nitrene generated from 3 benzyl 4 phenyl 1,2,4 oxadiazolone 5 by either pyrolysis or photolysis
NMR spin-spin coupling constants between vinyl protons in cyclopentadiene, 1,3-cyclohexadiene and 1-3-cyclooctadiene from spectrum analysis
Space shuttle abort stage separation wind tunnel tests of orbiter and booster vehicles - booster proximity data, Mach number 3
Static stability and control effectiveness characteristics of two 0.004 scale models of the vehicle 3 configuration are reported. The components investigated consisted of a single aft body, vertical/rudder, OMS pods with two interchangeable wings, four interchangeable forward bodies, four trimmers, and a spoiler. The test was conducted in 14 x 14 inch trisonic wind tunnel over a Mach number range from 0.6 to 4.96. Angles of attack from 0 to 60 degrees and angles of sideslip from -10 to 10 degrees at 0, 10, 20,30, and 40 degrees angle of attack were tested. Elevon, body flap, and speed brake deflection composed the parametric considerations. No grit was placed on the models during the test. The tabulated source data and incremental data figures are presented.
Power subsystem cost/weight tradeoffs are discussed for the Venus probe spacecraft. The cost estimations of power subsystem units were based upon DSCS-2, DSP, and Pioneer 10 and 11 hardware design and development and manufacturing experience. Parts count and degree of modification of existing hardware were factored into the estimate of manufacturing and design and development costs. Cost data includes sufficient quantities of units to equip probe bus and orbiter versions. It was based on the orbiter complement of equipment, but the savings in fewer slices for the probe bus balance the cost of the different probe bus battery. The preferred systems for the Thor/Delta and for the Atlas/Centaur are discussed. The weights of the candidate designs were based upon slice or tray weights for functionally equivalent circuitry measured on existing hardware such as Pioneers 10 and 11, Intelsat 3, DSCS-2, or DSP programs. Battery weights were based on measured cell weight data adjusted for case weight or off-the-shelf battery weights. The solar array weight estimate was based upon recent hardware experience on DSCS-2 and DSP arrays.
The BOPACE 3-D is a finite element computer program, which provides a general family of three-dimensional isoparametric solid elements, and includes a new algorithm for improving the efficiency of the elastic-plastic-creep solution procedure. Theoretical, user, and programmer oriented sections are presented to describe the program.
Modifications and additions incorporated into the BOPACE 3-D program are described. Updates to the program input data formats, error messages, file usage, size limitations, and overlay schematic are included.
The stage work distribution among the three stages was very close to the design value. The specific work output-mass flow characteristics of the three stages were closely matched. The efficiency of the 3 1/2 stage turbine at design specific work output and design speed was within 0.008 of the estimated value, and this agreement was felt to demonstrate the adequacy of the prediction method in the high stage loading factor regime.
The development of the module concepts are reviewed, and a number of functional elements are listed. Other areas examined include some of the following; (1) mission operations; (2) environmental control and life support subsystems concepts; (3) thermal heat rejection; (4) space radiation effect analysis; and (5) satellite power system test requirements.
The ascent opeational flight profile for the space transportation system 1 flight is designed (1) to limit the maximum undispersed dynamic pressure to 580 lb/sq ft, (2) to follow the design load indicator profiles where q alpha is a specified profile and q beta is desired to be as close to zero as passible, and (3) to maximize nominal and abort performance. Significant trajectory parameters achieved are presented. A maximum dynamic pressure of 575 lb/sq ft was achieved, a minimum q alpha of -2187 lb-deg/sq ft was achieved, and q beta was limited to approximately + or - 100 lb-deg/sq ft in the high q region of the trajectory. The trajectory performance allows a press to main engine cutoff capability with one space shuttle main engine out at 262 seconds ground elapsed time. The orbital maneuvering system burns achieve a final orbit of 150.9 x 149.9 x 149.8 n. mi. and the desired inclination of 40.3 degrees.