Fiscal year 1973 scientific and technical reports, articles, papers, and presentations

Formal NASA technical reports, papers published in technical journals, and presentations by MSFC personnel in FY73 are presented. Papers of MSFC contractors are also included

Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 141)

This special bibliography lists 267 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1975

Additive Manufacturing Research and Applications

This Special Issue book covers a wide scope in the research field of 3D-printing, including: the use of 3D printing in system design; AM with binding jetting; powder manufacturing technologies in 3D printing; fatigue performance of additively manufactured metals, such as the Ti-6Al-4V alloy; 3D-printing methods with metallic powder and a laser-based 3D printer; 3D-printed custom-made implants; laser-directed energy deposition (LDED) process of TiC-TMC coatings; Wire Arc Additive Manufacturing; cranial implant fabrication without supports in electron beam melting (EBM) additive manufacturing; the influence of material properties and characteristics in laser powder bed fusion; Design For Additive Manufacturing (DFAM); porosity evaluation of additively manufactured parts; fabrication of coatings by laser additive manufacturing; laser powder bed fusion additive manufacturing; plasma metal deposition (PMD); as-metal-arc (GMA) additive manufacturing process; and spreading process maps for powder-bed additive manufacturing derived from physics model-based machine learning

On non-invasive ultrasonic flowmeasurement

This thesis is concerned with non-invasive ultrasonic flow measurement, using the transit time principle. The errors associated with the transit-time flowmeter are investigated and a design of flowmeter is suggested. A theoretical and experimental study of the transmission of sound through pipe walls is carried out where it is shown that advantage can be taken of the excitation of Lamb modes. A design of transducer arrangement is made from the results of the work. A solution to the difficult problem of measuring very small times is provided in the form of a novel vernier timing system. The benefits and disadvantages of this timing system are discussed along with the design aspects of other electronic circuits required in the construction of the flowmeter. The flawmeter has been built and tested in the laboratory and is shown to be highly repeatable and accurate. The results of testing the flowmeter compare favourably with tests conducted on a commercial instrument. Improvements to the design and construction and suggestions for further work are given

Aeronautical Engineering: A continuing bibliography with indexes

This bibliography lists 512 reports, articles and other documents introduced into the NASA scientific and technical information system in April 1982

Aerospace Medicine and Biology: A cumulative index to the 1974 issues of a continuing bibliography

This publication is a cumulative index to the abstracts contained in supplements 125 through 136 of Aerospace Medicine and Biology: A Continuing Bibliography. It includes three indexes--subject, personal author, and corporate source

Aerospace Medicine and Biology: A continuing bibliography with indexes, (supplement 154), May 1976

This bibliography lists 253 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1976

Phase investigation of zirconia fibers and their applications on solid oxide fuel cells (SOFCs)

Pure zirconia nanofibers were fabricated by electrospinning zirconia-polymer precursor and subsequent annealing. Fiber properties such as polymer decomposition, crystallization formation, phase transformation, surface morphologies, etc., were investigated by various techniques, including thermogravimetric analysis (TGA) and differential thermal analysis (DTA), high temperature differential scanning calorimeter (HTDSC), powder X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), etc. It was found the crystallization of as-spun fibers started at 450 °C and the initial crystallized zirconia phase was tetragonal (t), which began transforming to monoclinic (m) phase at 650 °C as evidenced by XRD; HTDSC showed at different thermal circles, the m-to-t transformation temperatures remained virtually unchanged while the reverse t-to-m temperatures systematically shifted from 924.9 to 978.6 °C as the progress of thermal circles; FESEM examinations revealed that fibers calcined to 1000 °C went through thermal grooving due to surface diffusion during heat treatment; fibers heated to 1370 °C formed the so-called “bamboo wires”, where volume diffusion was the dominant driving force. A novel route to fabricate nanofiber-based anodes for solid oxide fuel cells (SOFCs) was also presented. Uniform YSZ nanofibers were first synthesized by electrospinning of 8YSZ dispersion. The fiber surfaces were then electrolessly plated with a layer of Ni after sintering. The Ni-YSZ nanofibers were slurry-coated on a commercial half cell as the anode and the cell performance was tested; the Ni content was quantified by XPS. A second cell with the same Ni content in the anode as the first one, prepared by conventional ball-milling of powders, was also fabricated and tested. We found the peak power density for the cell with the fiber-based anode is twice of that with the powder-based anode; the FESEM images of the two cells showed that the fiber-coated anode mainly consisted of nanofibers, which formed an interconnected network within the anode; on the other hand, the particles in the powder-coated anode formed sphere-like granules that are unorganized and are not well-connected, which will not be advantageous for anode functionality. In the end we came up with two anode models that are based on FESEM observations and they explained the superiority of the fiber-based anode

The 1972 Summer Institute for Biomedical Engineering

Design of hemoglobin tester, flow ventilation systems, blood viscometer, isotope handling equipment, and blood pressure measuring devic