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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.

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At least 361 records · Page 20
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Cryogenic optical systems and instruments IV; Proceedings of the Meeting, San Diego, CA, July 10-12, 1990

Consideration is given to cryogenic system design and optical technology; cryogenic instruments, sensors, and detectors; space cryogenic dewars and coolers; and cryogenic mechanisms, testing, and structures. Particular attention is given to mission optimization of the Space Infrared Telescope Facility (SIRTF), alternative aperture stop position designs for SIRTF, scaling laws for lightweight optics, evaluation of a far-infrared Ge:Ga multiplexed detector array, cryogenic limb array etalon spectrometer calibration, reliability growth of coolers for advanced optical systems and instruments, flight-qualified solid argon cooler for the BBXRT instrument, precision mechanisms for optical alignments at cryogenic temperatures, versatile cryogenic rotary-positioning systems, and optical alignments of the Cosmic Background Explorer observatory.

Melugin, Ramsey K.↗
NASA NTRS1991

1991 IEEE Annual Conference on Nuclear and Space Radiation Effects, 28th, San Diego, CA, July 15-19, 1991, Proceedings

Various papers on nuclear science are presented. The general topics addressed are: basic mechanisms of radiation effects, dosimetry and energy-dependent effects, isolation technologies, device radiation response and hardening, microcircuit radiation response and hardening, single-event phenomena, hardness assurance and testing techniques, spacecraft charging, space environments and effects.

Millward, Douglas G.↗
NASA NTRS1991

X-ray/EUV optics for astronomy, microscopy, polarimetry, and projection lithography; Proceedings of the Meeting, San Diego, CA, July 9-13, 1990

Topics discussed in this issue include the fabrication of multilayer X-ray/EUV coatings; the design, characterization, and test of multilayer X-ray/EUV coatings; multilayer X-ray/EUV monochromators and imaging microscopes; X-ray/EUV telescopes; the test and calibration performance of X-ray/EUV instruments; XUV/soft X-ray projection lithography; X-ray/EUV space observatories and missions; X-ray/EUV telescopes for solar research; X-ray/EUV polarimetry; X-ray/EUV spectrographs; and X-ray/EUV filters and gratings. Papers are presented on the deposition-controlled uniformity of multilayer mirrors, interfaces in Mo/Si multilayers, the design and analysis of an aspherical multilayer imaging X-ray microscope, recent developments in the production of thin X-ray reflecting foils, and the ultraprecise scanning technology. Consideration is also given to an active sun telescope array, the fabrication and performance at 1.33 nm of a 0.24-micron-period multilayer grating, a cylindrical proportional counter for X-ray polarimetry, and the design and analysis of the reflection grating arrays for the X-Ray Multi-Mirror Mission.

Hoover, Richard B.↗
NASA NTRS1990

Intermetallic matrix composites; Proceedings of the MRS Symposium, San Francisco, CA, Apr. 18-20, 1990

The present volume on intermetallic matrix composites discusses the modeling, processing, microstructure/property relationships, and compatibility of intermetallic matrix composites. Attention is given to models for the strength of ductile matrix composites, innovative processing techniques for intermetallic matrix composites, ductile phase toughening of brittle intermetallics, and reactive synthesis of NbAl3 matrix composites. Topics addressed include solidification processing of NbCr2 alloys, Ta and Nb reinforced MoSi2, the microstructure and mechanical behavior of Ni3Al-matrix composites, and ductile-phase toughening of Cr3Si with chromium. Also discussed are dislocation morphologies in TiB2/NiAl, the development of highly impact resistant NiAl matrix composites, the effect of notches on the fatigue life of the SCS-6Ti3Al composite, and the chemical stability of fiber-metal matrix composites.

Anton, D. L.↗
NASA NTRS1991

Fiber optic and laser sensors VIII; Proceedings of the Meeting, San Jose, CA, Sept. 17-19, 1990

This issue presents topics on the advances in fiber-optic sensor technology, fiber-optic gyroscope, fiber-optic position and pressure sensors, fiber-optic magnetic and temperature sensors, and generic fiber-optic sensors. Papers included are on a novel analog phase tracker for interferometric fiber-optic sensor applications, recent development status of fiber-optic sensors in China, the magnetic-field sensitivity of depolarized fiber-optic gyros, a depolarized fiber-optic gyro for future tactical applications, fiber-optic position transducers for aircraft controls, and a metal embedded optical-fiber pressure sensor. Attention is also given to a fiber-optic magnetic field sensor using spectral modulation encoding, a bare-fiber temperature sensor, an interferometric fiber-optic accelerometer, improvement of specular reflection pyrometer, a theoretical analysis of two-mode elliptical-core optical fiber sensors, and a fiber probe for ring pattern.

Depaula, Ramon P.↗
NASA NTRS1992

Non-LTE radiating acoustic shocks and Ca II K2V bright points

We present, for the first time, a self-consistent solution of the time-dependent 1D equations of non-LTE radiation hydrodynamics in solar chromospheric conditions. The vertical propagation of sinusoidal acoustic waves with periods of 30, 180, and 300 s is calculated. We find that departures from LTE and ionization recombination determine the temperature profiles of the shocks that develop. In LTE almost all the thermal energy goes into ionization, so the temperature rise is very small. In non-LTE, the finite transition rates delay the ionization to behind the shock front. The compression thus goes into thermal energy at the shock front leading to a high temperature amplitude. Further behind the shock front, the delayed ionization removes energy from the thermal pool, which reduces the temperature, producing a temperature spike. The 180 s waves reproduce the observed temporal changes in the calcium K line profiles quite well. The observed wing brightening pattern, the violet/red peak asymmetry and the observed line center behavior are all well reproduced. The short-period waves and the 5 minute period waves fail especially in reproducing the observed behavior of the wings.

Carlsson, Mats↗
NASA NTRS1992

International SAMPE Symposium and Exhibition, 37th, Anaheim, CA, Mar. 9-12, 1992, Proceedings

The present conference discusses the industrial and transportation markets for advanced composites, novel NASA and military applications of advanced materials, composite space structures, sandwich structures, composite tooling and processing, advanced epoxy compositions, composites repair, commercial applications of advanced resins, metal-matrix composites, adhesive compositions, ultrahigh-temperature composites, failure analyses, testing methods for composites, and bismaleimides and polyimides. Also discussed are composite structures design, innovations in composite reinforcement, nonautoclave-processed composites, molecular composites, design and manufacture processes with thermoplastics, automation in manufacturing, technologies for large component fabrication, damage-limitation design practices, thermoplastic-matrix composites, industrial applications of composites, and process controls in composites manufacturing.

Grimes, Glenn C.↗
NASA NTRS1991

Free-space laser communication technologies III; Proceedings of the Meeting, Los Angeles, CA, Jan. 21, 22, 1991

The present volume on free-space laser communication technologies discusses system analysis, performance, and applications, pointing, acquisition, and tracking in beam control, laboratory demonstration systems, and transmitter and critical component technologies. Attention is given to a space station laser communication transceiver, meeting intersatellite links mission requirements by an adequate optical terminal design, an optical approach to proximity-operations communications for Space Station Freedom, and optical space-to-ground link availability assessment and diversity requirements. Topics addressed include nonmechanical steering of laser beams by multiple aperture antennas, a free-space simulator for laser transmission, heterodyne acquisition and tracking in a free-space diode laser link, and laser terminal attitude determination via autonomous star tracking. Also discussed are stability considerations in relay lens design for optical communications, liquid crystals for lasercom applications, and narrowband optical interference filters.

Begley, David L.↗
NASA NTRS1991

AIAA/NASA International Symposium on Space Information Systems, 2nd, Pasadena, CA, Sept. 17-19, 1990, Proceedings. Vols. 1 & 2

These proceedings overview major space information system projects and lessons learned from current missions. Other topics include the science information system requirements for the 1990s, an information systems design approach for major programs, the technology needs and projections, the standards for space data information systems, the artificial intelligence technology and applications, international interoperability, and spacecraft data systems and architectures advanced communications. Other topics include the software engineering technology and applications, the multimission multidiscipline information system architectures, the distributed planning and scheduling systems and operations, and the computer and information systems architectures. Paper presented include prospects for scientific data analysis systems for solar-terrestrial physics in the 1990s, the Columbus data management system, data storage technologies for the future, the German aerospace research establishment, and launching artificial intelligence in NASA ground systems.

Tavenner, Leslie A.↗
NASA NTRS1993

X-ray detector physics and applications; Proceedings of the Meeting, San Diego, CA, July 23, 24, 1992

Recent developments in X-ray and hard X-ray imaging detector, high-intensity sources, hard X-ray imaging optics, calibration, and detection technologies are discussed. Particular attention is given to a high-MTF X-ray image intensifier, application of monolithic CdZnTe linear solid state ionization detectors for X-ray imaging, magnetic response of high-Tc superconductors to X-ray radiation and detection of X-rays, laboratory soft X-ray source with foil target, detection of explosive materials using nuclear radiation, energy response of astronomical CCD X-ray detectors, calibration techniques for high-flux X-ray detectors, fabrication of grazing-incidence optics using flow-polishing techniques, and numerical simulations for capillary-based X-ray optics. (No individual items are abstracted in this volume)

Hoover, Richard B.↗
NASA NTRS1991

Propagation of high-energy laser beams through the earth's atmosphere II; Proceedings of the Meeting, Los Angeles, CA, Jan. 21-23, 1991

Consideration is given to turbulence at the inner scale, modeling turbulent transport in laser beam propagation, variable wind direction effects on thermal blooming correction, realistic wind effects on turbulence and thermal blooming compensation, wide bandwidth spectral measurements of atmospheric tilt turbulence, remote alignment of adaptive optical systems with far-field optimization, focusing infrared laser beams on targets in space without using adaptive optics, and a simplex optimization method for adaptive optics system alignment. Consideration is also given to ground-to-space multiline propagation at 1.3 micron, a path integral approach to thermal blooming, functional reconstruction predictions of uplink whole beam Strehl ratios in the presence of thermal blooming, and stability analysis of semidiscrete schemes for thermal blooming computation.

Ulrich, Peter B.↗
NASA NTRS1993

Cryogenic optical systems and instruments V; Proceedings of the Meeting, San Diego, CA, July 23, 24, 1992

Topics discussed in this volume include cryogenic system design and optical technology; cryogenic instruments; cryogenic/IR mechanisms, testing, and performance; and space cryogenic dewars and coolers. Papers included are on the SIRTF cryooptics technology plan, the development of the SPIRIT III sensor, the design of a rapidly cooled cryogenic mirror, the cryogenic Michelson interferometer on the Space Shuttle, a reflective optical system for a hemispherical field radiometer, and infrared filters for cryogenic radiometers. Attention is also given to the development of a variable-profile scan mirror mechanism, a direct-drive digitally commutated filter wheel positioning system for cryogenic optical applications, a high-performance chopping secondary mirror for infrared astronomy, recent developments in compressor-based Joule-Thomson cooling, a radiative cryogenic cooler for the pressure modulator IR radiometer, and SIRTF thermal design modifications to increase lifetime.

Melugin, Ramsey K.↗
NASA NTRS1993

AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 34th and AIAA/ASME Adaptive Structures Forum, La Jolla, CA, Apr. 19-22, 1993, Technical Papers. Pts. 1-6

Topics addressed include the prediction of helicopter component loads using neural networks, spacecraft on-orbit coupled loads analysis, hypersonic flutter of a curved shallow panel with aerodynamic heating, thermal-acoustic fatigue of ceramic matrix composite materials, transition elements based on transfinite interpolation, damage progression in stiffened composite panels, a direct treatment of min-max dynamic response optimization problems, and sources of helicopter rotor hub inplane shears. Also discussed are dynamics of a layered elastic system, confidence bounds on structural reliability, mixed triangular space-time finite elements, advanced transparency development for USAF aircraft, a low-velocity impact on a graphite/PEEK, an automated mode-tracking strategy, transonic flutter suppression by a passive flap, a nonlinear response of composite panels to random excitation, an optimal placement of elastic supports on a simply supported plate, a probabilistic assessment of composite structures, a model for mode I failure of laminated composites, a residual flexibility approach to multibody dynamics,and multilayer piezoelectric actuators.

Source record↗
NASA NTRS1991

Numerical methods in laminar and turbulent flow; Proceedings of the 7th International Conference, Stanford Univ., CA, July 15-19, 1991. Vol. 7, pts. 1 & 2

Consideration is given to the impulse response of a laminar boundary layer and receptivity; numerical transition to turbulence in plane Poiseuille flow; large eddy simulation of turbulent wake flow; a viscous model and loss calculation of a multisplitter cascade; vortex initiation during dynamic stall of an airfoil; a numerical analysis of isothermal flow in a combustion chamber; and compressible flow calculations with a two-equation turbulence model and unstructured grids. Attention is also given to a 2D calculation of a buoyant flow around a burning sphere, a fast multigrid method for 3D turbulent incompressible flows, a streaming flow induced by an oscillating cascade of circular cylinders, an algebraic multigrid scheme for solving the Navier-Stokes equations on unstructured meshes; and nonlinear coupled multigrid solutions to thermal problems employing different nodal grid arrangements and convective transport approximations.

Taylor, C.↗
NASA NTRS1991

Infrared technology XVII; Proceedings of the Meeting, San Diego, CA, July 22-26, 1991

Recent advances in IR technologies and their application to all types of IR systems are reported focusing on the JPL Space Infrared Telescope Facility (SIRTF), JPL instruments and systems for observation of earth and the atmosphere, staring arrays and thermal imaging, ten-year updates of IR techniques, infrared in the USSR, simulation and testing, focal-plane and optical technologies, and military and scientific applications. Particular attention is given to SIRTF stray light analysis, SIRTF focal-plane technologies, long-wave IR detectors based on III-V materials, IR lidars for atmospheric remote sensing, a firefly system concept, a high-fill-factor monolithic IR image sensor, atmospheric laser-transmission tables simply generated, ORION semiconductor optical detectors, postprocessing of thermograms in IR nondestructive testing, evaluation of the IR signature of dynamic air targets, the current status of InGaAs detector arrays for 1-3 microns, a dual-band optical system for IR multicolor signal processing, and blackbody radiators for field calibration.

Andresen, Bjorn F.↗
NASA NTRS1993

Multilayer and grazing incidence X-ray/EUV optics for astronomy and projection lithography; Proceedings of the Meeting, San Diego, CA, July 19-22, 1992

The present volume on multilayer and grazing incidence X-ray/EUV optics for astronomy and projection lithography discusses AXAF grazing incidence mirrors, the theory and high throughput optics of grazing incidence optics, multilayer mirror fabrication and characterization, and multilayer optics for X-ray projection lithography. Attention is given to the VETA-I X-ray detection system, a motion detection system for AXAF X-ray ground testing, image analysis of the AXAF VETA-I X-ray mirror, and optical constants from mirror reflectivities measured at synchrotrons. Topics discussed include the application of aberration theory to calculate encircled energy of Wolter I-II telescopes, W/C multilayers deposited on plastic films, nonspecular X-ray scattering from Si/Mo multilayers, and multilayer thin-film design as FUV polarizers. Also discussed are thin-film filter lifetesting results in the EUV, chromospheric and coronal observations with multilayer optics, present and future requirements of soft X-ray projection lithography, and the imaging Schwarzschild multilayer X-ray microscope.

Hoover, Richard B.↗
NASA NTRS1992

Multilayer and grazing incidence X-ray/EUV optics; Proceedings of the Meeting, San Diego, CA, July 22-24, 1991

The present conference discusses the Advanced X-ray Astrophysics Facility (AXAF) calibration by means of synchrotron radiation and its X-ray reflectivity, X-ray scattering measurements from thin-foil X-ray mirrors, lobster-eye X-ray optics using microchannel plates, space-based interferometry at EUV and soft X-ray wavelengths, a water-window imaging X-ray telescope, a graded d-spacing multilayer telescope for high energy X-ray astronomy, photographic films for the multispectral solar telescope array, a soft X-ray ion chamber, and the development of hard X-ray optics. Also discussed are X-ray spectroscopy with multilayered optics, a slit aperture for monitoring X-ray experiments, an objective double-crystal spectrometer, a Ly-alpha coronagraph/polarimeter, tungsten/boron nitride multilayers for XUV optical applications, the evaluation of reflectors for soft X-ray optics, the manufacture of elastically bent crystals and multilayer mirrors, and selective photodevices for the VUV.

Hoover, Richard B.↗
NASA NTRS1993

Processing, electrical and microwave properties of sputtered Tl-Ca-Ba-Cu-O superconducting thin films

A reproducible fabrication process has been established for TlCaBaCuO thin films on LaAlO3 substrates by RF magnetron sputtering and post-deposition processing methods. Electrical transport properties of the thin films were measured on patterned four-probe test devices. Microwave properties of the films were obtained from unloaded Q measurements of all-superconducting ring resonators. This paper describes the processing, electrical and microwave properties of Tl2Ca1Ba2Cu2O(x) 2122-plane phase thin films.

Subramanyam, G.↗