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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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NASA NTRS1992

Glass sample preparation and performance investigations

This final report details the work performed under this delivery order from April 1991 through April 1992. The currently available capabilities for integrated optical performance modeling at MSFC for large and complex systems such as AXAF were investigated. The Integrated Structural Modeling (ISM) program developed by Boeing for the U.S. Air Force was obtained and installed on two DECstations 5000 at MSFC. The structural, thermal and optical analysis programs available in ISM were evaluated. As part of the optomechanical engineering activities, technical support was provided in the design of support structure, mirror assembly, filter wheel assembly and material selection for the Solar X-ray Imager (SXI) program. As part of the fabrication activities, a large number of zerodur glass samples were prepared in different sizes and shapes for acid etching, coating and polishing experiments to characterize the subsurface damage and stresses produced by the grinding and polishing operations. Various optical components for AXAF video microscope and the x-ray test facility were also fabricated. A number of glass fabrication and test instruments such as a scatter plate interferometer, a gravity feed saw and some phenolic cutting blades were fabricated, integrated and tested.

Johnson, R. Barry↗

NASA NTRS1990

The NASA Space Life Sciences Training Program - Preparing the way

Attention is given to the goals and methods adopted in the NASA Space Life Sciences Training Program (SLSTP) for preparing scientists and engineers for space-related life-sciences research and operations. The SLSTP is based on six weeks of projects and lectures which give an overview of payload processing and experiment flow in the space environment. The topics addressed in the course of the program include descriptions of space vehicles, support hardware, equipment, and research directions. Specific lecture topics include the gravity responses of plants, mission integration of a flight experiment, and the cardiovascular deconditioning. The SLSTP is shown to be an important part of the process of recruiting and training qualified scientists and engineers to support space activities.

Biro, Ronald↗

NASA NTRS1992

Preparing safety data packages for experimenters using the Get Away Special (GAS) carrier system

The implementation of NSTS 1700.7B and more forceful scruntiny of data packages by the Johnson Space Flight Center (JSC) lead to the development of a classification policy for GAS/CAP payloads. The purpose of this policy is to classify experiments using the carrier system so that they receive an appropriate level of JSC review (i.e., one or multiphase reviews). This policy is based on energy containment to show inherent payload safety. It impacts the approach to performing hazard analyses and the nature of the data package. This paper endeavors to explain the impact of this policy as well as the impact of recent JSC as well as Kennedy Space Flight Center (KSC) 'interpretations' of existing requirements. The GAS canister does adequately contain most experiments when flown in the sealed configuration (however this must be shown, not merely stated). This paper also includes data package preparation guidelines for those experiments that require an opening door which often present unique safety issues.

Kosko, Jerome↗

NASA NTRS1993

Crosslinked polyimides prepared from N-(3-ethynylphenyl)maleimide

The compound N-(3-ethynylphenyl)maleimide (NEPMI) was used to prepare thermally stable, glassy polyimides which did not exhibit glass transition temperatures below 500 C. NEPMI was blended with the maleimide of methylene dianiline (BMI) and heated to form the polyimide. NEPMI was also mixed with Thermid 600 R, a commercially available bisethynyl oligomeric material, and heated to form a thermally stable, glassy polyimide. Lastly, NEPMI was blended with both BMI and Thermid 600 R to form thermally stable, glassy polyimides.

Gerber, Margaret K.↗

NASA NTRS1993

Polyimides prepared from 3,5-diamino benzo trifluoride

High performance, thermooxidatively stable polyimides are prepared by reacting aromatic diamines with pendant trifluoromethyl groups and dianhydrides in an amide solvent to form a poly(amic acid), followed by cyclizing the poly(amic acid) to form the corresponding polyimide.

Gerber, Margaret K.↗

NASA NTRS1993

Diphenylmethane-containing dianhydride and polyimides prepared therefrom

A high temperature stable, highly optically transparent-to-colorless, low dielectic linear aromatic polyimide is prepared by reacting an aromatic diamine with 3,3'bis (3,4-dicarboxyphenoxy) diphenylmethane dianhydride in an amide solvent to form a linear aromatic polyamic acid. This polyamic acid is then cyclized to form the corresponding polyimide.

St.clair, Anne K.↗

NASA NTRS1930

Fuel Vapor Pressures and the Relation of Vapor Pressure to the Preparation of Fuel for Combustion in Fuel Injection Engines

This investigation on the vapor pressure of fuels was conducted in connection with the general research on combustion in fuel injection engines. The purpose of the investigation was to study the effects of high temperatures such as exist during the first stages of injection on the vapor pressures of several fuels and certain fuel mixtures, and the relation of these vapor pressures to the preparation of the fuel for combustion in high-speed fuel injection engines.

Joachim, William F↗

NASA NTRS1994

Preparation And Analysis Of Specimens Of Ablative Materials

Procedure for chemical analysis of specimens of silicone-based ablative thermal-insulation materials SLA-561 and MA25 involves acid digestion of specimens to prepare them for analysis by inductively-coupled-plasma/atomic-emission spectroscopy (ICP/AES). In comparison with atomic-absorption spectroscopy (AAS), ICP/AES is faster and more accurate than AAS. Results of analyses stored in data base, used to trace variations in concentrations of chemical elements in materials during long-term storage, and used in timely manner in investigations of failures. Acid-digestion portion of procedure applied to other thermal-insulation materials containing room-temperature-vulcanizing silicones and enables instrumental analysis of these materials.

Solomon, William C.↗

NASA NTRS1993

New aromatic activated dihalides and bisphenol monomers for the preparation of novel poly(arylene ethers)

The goal of this research program was to synthesize a series of unique monomers of type I to be utilized at NASA-Langley in the preparation of new poly(arylene ether ketones), poly(arylene ether ketosulfones), and poly(arylene ether ketophosphine oxides). These A-A and A-B monomer systems, which possess activated aryl halide and/or phenolic end groups, are accessible via condensation reactions of appropriately substituted aryl acetonitrile carbanions with activated aryl dihalides followed by oxidative decyanation.

Wolfe, James F.↗

NASA NTRS1993

Preparing the DSN operations concepts

Operations concepts are prepared to support a specific application and can, therefore, be classified accordingly. Studies of NASA and military operations concepts suggest three major types: data services, customer services, and systems oriented. Data services concepts concentrate on data types (e.g., telemetry and command) and how these data are processed and delivered to the user. Such concepts are normally used by data-processing centers to describe data-coding schemes and data formats. Customer services concepts concentrate on the customers' requirements and describe how these requirements are met using the systems available to the operation. Project centers use such concepts to describe the various types of data as they flow from the source (e.g., a spacecraft) to the end user (i.e., the customer). Systems oriented concepts concentrate on the use of systems for processing and delivering customer data. This paper examines the latter type and the 'concepts' that are inherent within them.

Salazar, A. J.↗

NASA NTRS1993

Estimating the Deep Space Network modification costs to prepare for future space missions by using major cost drivers

This paper develops a cost model to do long range planning cost estimates for Deep Space Network (DSN) support of future space missions. The paper focuses on the costs required to modify and/or enhance the DSN to prepare for future space missions. The model is a function of eight major mission cost drivers and estimates both the total cost and the annual costs of a similar future space mission. The model is derived from actual cost data from three space missions: Voyager (Uranus), Voyager (Neptune), and Magellan. Estimates derived from the model are tested against actual cost data for two independent missions, Viking and Mariner Jupiter/Saturn (MJS).

Remer, Donald S.↗

NASA NTRS1994

Preparations for flight research to evaluate actuated forebody strakes on the F-18 high-alpha research vehicle

As part of the NASA High-Angle-of-Attack Technology Program (HATP), flight tests are currently being conducted with a multi-axis thrust vectoring system applied to the NASA F-18 High Alpha Research Vehicle (HARV). A follow-on series of flight tests with the NASA F-18 HARV will be focusing on the application of actuated forebody strake controls. These controls are designed to provide increased levels of yaw control at high angles of attack where conventional aerodynamic controls become ineffective. The series of flight tests are collectively referred to as the Actuated Nose Strakes for Enhanced Rolling (ANSER) Flight Experiment. The development of actuated forebody strake controls for the F-18 HARV is discussed and a summary of the ground tests conducted in support of the flight experiment is provided. A summary of the preparations for the flight tests is also provided.

Murri, Daniel G.↗

NASA NTRS1994

A direct process for preparing semi-crystalline polyimides

The invention is a direct process for preparing semi-crystalline polyimides. This process comprises the steps of: providing a polar aprotic solvent, adding a dianhydride and a diamine to the solvent to form a mixture, stirring the mixture at ambient temperature, and adding glacial acetic acid to the mixture to provide a ratio of polar aprotic solvent to glacial acetic acid which ranges from about 90 to 10 to about 75 to 25 by volume to form a solution. The solution was heated to a range from about 110 C to about 140 C to form a polyimide precipitate. The polyimide precipitate was recovered as a semi-crystalline polyimide powder.

Chang, Alice C.↗

NASA NTRS1995

CD-ROM preparation: An overview and guide

A primer on the options and procedures involved in producing CD-ROM products in a small to medium sized business operation is presented in language that persons with a minimal technical background can easily understand. The capabilities, limitations, and standards of CD-ROM technology are surveyed. Emphasis is placed on CD-ROM production, especially upon design, data conversion to an electronic medium, data file preparation, the use of vendors, and the steps for in-house production of CD-ROM products.

Daniel, Ralph E.↗

NASA NTRS1995

Verification of surface preparation for adhesive bonding

A survey of solid rocket booster (SRB) production operations identified potential contaminants which might adversely affect bonding operations. Lap shear tests quantified these contaminants' effects on adhesive strength. The most potent contaminants were selected for additional studies on SRB thermal protection system (TPS) bonding processes. Test panels were prepared with predetermined levels of contamination, visually inspected using white and black light, then bonded with three different TPS materials over the unremoved contamination. Bond test data showed that white and black light inspections are adequate inspection methods for TPS bonding operations. Extreme levels of contamination (higher than expected on flight hardware) had an insignificant effect on TPS bond strengths because of the apparent insensitivity of the adhesive system to contamination effects, and the comparatively weak cohesive strength of the TPS materials.

Myers, Rodney S.↗

NASA NTRS1995

Preparation Of Strong, Dense Potassium Beta''-Alumina Ceramic

Improved process for making mechanically strong, dense, phase-pure potassium beta''-alumina solid electrolyte (K-BASE) results in material superior to all previous K-BASE preparations and similar to commercial Na-BASE in strength, phase purity and high-temperature ionic conductivity. Potassium-based alkali-metal thermal-to-electric conversion (AMTEC) cells expected to operate efficiently at lower heat-input temperatures and lower rejection temperatures than sodium-based AMTEC cells, making them appropriate for somewhat different applications.

Williams, Roger M.↗

NASA NTRS1995

Percolation effect in thick film superconductors: Using a Bi(Pb)SrCaCuO based paste to prepare a superconducting planar transformer

A thick film superconductor paste has been developed to study the properties of granulated superconductor materials, to observe the percolation effect and to confirm the theory of the conducting mechanism in the superconducting thick films. This paste was also applied to make a superconducting planar transformer. Due to the T(sub c) and advantageous current density properties the base of the past was chosen to be of Bi(Pb)SrCaCu) system. For contacts a conventional Ag/Pt paste was used. The critical temperature of the samples were between 110 K and 115 K depending on the printed layer thickness. The critical current density -at the boiling temperature of the liquid He- was between 200 - 300 A/sq cm. The R(T) and V(I) functions were measured with different parameters. The results of the measurements have confirmed the theory of conducting mechanism in the material. The percolation structure model has been built and described. As an application, a superconducting planar thick film transformer was planned and produced. Ten windings of the transformer were printed on one side of the alumina substrate and one winding was printed on the other side. The coupling between the two sides was possible through the substrate. The samples did not need special drying and firing parameters. After the preparation, the properties of the transformer were measured. The efficiency ans the losses were determined. Finally, some fundamental advantages and problems of the process were discussed.

Sali, Robert↗

NASA NTRS1995

A Dry Powder Process for Preparing Uni-Tape Prepreg from Polymer Powder Coated Filamentary Towpregs

A process for preparing uni-tape prepreg from polymer powder coated filamentary towpregs is provided. A plurality of polymer powder coated filamentary towpregs are provided. The towpregs are collimated so that each towpreg is parallel. The sandwich is heated to a temperature wherein the polymer flows and intimately contacts the filaments and pressure is repeatedly applied perpendicularly to the sandwich with a longitudinal oscillating action wherein the filaments move apart and the polymer wets the filaments forming a uni-tape prepreg. The uni-tape prepreg is subsequently cooled.

Wilkinson, Steven P.↗