Advanced electro-optical imaging techniques

The papers presented at the symposium are given which deal with the present state of sensors, as may be applicable to the Large Space Telescope (LST) program. Several aspects of sensors are covered including a discussion of the properties of photocathodes and the operational imaging camera tubes

Fluid quantity gaging

A system for measuring the mass of liquid in a tank on orbit with 1 percent accuracy was developed and demonstrated. An extensive tradeoff identified adiabatic compression as the only gaging technique that is independent of gravity or its orientation, and of the size and distribution of bubbles in the tank. This technique is applicable to all Earth-storable and cryogenic liquids of interest for Space Station use, except superfluid helium, and can be applied to tanks of any size, shape, or internal structure. Accuracy of 0.2 percent was demonstrated in the laboratory, and a detailed analytical model was developed and verified by testing. A flight system architecture is presented that allows meeting the needs of a broad range of space fluid systems without custom development for each user

Conceptual design and analysis of a large antenna utilizing electrostatic membrane management

Conceptual designs and associated technologies for deployment 100 m class radiometer antennas were developed. An electrostatically suspended and controlled membrane mirror and the supporting structure are discussed. The integrated spacecraft including STS cargo bay stowage and development were analyzed. An antenna performance evaluation was performed as a measure of the quality of the membrane/spacecraft when used as a radiometer in the 1 GHz to 5 GHz region. Several related LSS structural dynamic models differing by their stiffness property (and therefore, lowest modal frequencies) are reported. Control system whose complexity varies inversely with increasing modal frequency regimes are also reported. Interactive computer-aided-design software is discussed

Advanced Energy Harvesting Technologies

Energy harvesting is the conversion of unused or wasted energy in the ambient environment into useful electrical energy. It can be used to power small electronic systems such as wireless sensors and is beginning to enable the widespread and maintenance-free deployment of Internet of Things (IoT) technology. This Special Issue is a collection of the latest developments in both fundamental research and system-level integration. This Special Issue features two review papers, covering two of the hottest research topics in the area of energy harvesting: 3D-printed energy harvesting and triboelectric nanogenerators (TENGs). These papers provide a comprehensive survey of their respective research area, highlight the advantages of the technologies and point out challenges in future development. They are must-read papers for those who are active in these areas. This Special Issue also includes ten research papers covering a wide range of energy-harvesting techniques, including electromagnetic and piezoelectric wideband vibration, wind, current-carrying conductors, thermoelectric and solar energy harvesting, etc. Not only are the foundations of these novel energy-harvesting techniques investigated, but the numerical models, power-conditioning circuitry and real-world applications of these novel energy harvesting techniques are also presented

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 122, December 1973

This special bibliography lists 343 reports, articles, and other documents introduced into the NASA scientific and technical information system in November 1973

Manipulated Electrochemical Surface Reactions Induced By Oscillatory Electric Potentials on Metal Based Electrodes

This research effort investigates the manipulation of surface electrochemical reactions induced by oscillating electric potentials on the surface of metal-based electrodes. Specifically, this research presents experimental data identifying modified electrochemical surface reactions caused by low magnitude electric potential oscillations on multilayered catalytic membranes and on implanted biometallic alloys. The scope of this effort consists of four major components: (1) perform an exhaustive literature review and analysis of the current understanding in applied surface electrochemistry and develop potential theoretical frameworks by which to interpret the experimental results; (2) identify the electrochemical manipulation via electrical oscillation while reacting nitric oxide on a multilayered ceramic membrane in combustion exhaust; (3) demonstrate that low magnitude electric potential oscillation are sufficient to induce corrosion of implanted biometallic alloys; (4) evaluate ambient electromagnetic radiation as a contributing factor to the complex corrosion of implanted ASTM F1537 CoCrMo.Although electrochemistry has been a driving force of many modern technologic advancements and the fundamental relations of electrochemistry have existed for over 100 years, current techniques do not adequately address the possibility for high frequency spatially and temporally varying electromagnetic potential fields and their effects on surface reactivity. Modern electrochemical theory remains focused on quasi-steady state reduction and oxidation reactions. Expanding upon existing theoretical models, such as the Newns-Anderson model for surface adsorbate systems, three feasible mechanisms of action are proposed by which spatially and temporally varying electromagnetic fields may interact to alter surface chemical reactions at the boundary of a metal-based electrode: direct shifting of the d-band center on the metallic surface, a photon-phonon interaction leading to the creation of a phonon-polariton, and/or the evolution of a complex three dimensional field with surface normal. When investigating a multilayered ceramic electrochemical catalytic membrane for automotive emission reduction, it was concluded that the presence of high frequency, low magnitude electric potential oscillations resulted in a manipulation of the predicted chemical pathway during the conversion of NO into diatomic nitrogen and oxygen. The electrical activity altered the initial surface electrochemical reaction toward the less probable formation of N2O, instead of NO2, ultimately resulting in greater NO reduction efficacy, compared to a Pt catalyst. Electrical stimulation (at 200 mVpp, \u3e25MHz) of ASTM F1537 CoCrMo within a simulated synovial fluid resulted in significant corrosion activity. The chemical composition of corrosion products grown via electrical stimulation match that of recovered in vivo corrosion products. The corrosion products contain primarily Cr2O3, CrO3, phosphates, molybdates, CrOH, and CoOH, with varying concentrations of Ca, P, and Co. Furthermore, this work demonstrates that the ambient electromagnetic field in a standard university laboratory can induce sufficient electrical activity to initiate the corrosion of ASTM F1537 CoCrMo in a simulated synovial fluid environment. Samples shielded from electrical activity did not demonstrate corrosion activity, whereas samples subjected to ambient electromagnetic activity showed formation of Cr2O3 and potentially CrO3 with significant concentrations of Ca, P, N, and Na. The work presented throughout this thesis provides foundational experimental data which identifies a novel electrochemical reaction manipulation phenomenon arising from temporally and spatially varying electromagnetic fields. This electrochemical phenomenon is believed to persist across a general electrochemical system and deserves significant future study

Development of ion jelly thin films for electrochemical devices

Dissertação para obtenção do Grau de Doutor em Química SustentávelIonic liquids (ILs) are promising materials which have been used in a wide range of applications. However, their major limitation is their physical state. In order to address this challenge, a self-supported IL-based material was developed by combining gelatine with an IL, originating a quasi-solid material named Ion Jelly (IJ). This is a light flexible material, dimensionally stable, with promising properties to develop safe and highly conductive electrolytes. This thesis is focused on the characterization of IJ films based on different ILs. The conductive mechanisms of IJ materials were studied using dielectric relaxation spectroscopy (DRS) in the frequency range 10-1−106 Hz. The study was complemented by differential scanning calorimetry (DSC) and pulsed field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. A glass transition was detected by DSC for all materials allowing to classify them as glass formers. From dielectric measurements, transport properties such as mobility and diffusion coefficients were extracted. Moreover, it was found that the diffusion coefficients and mobility are similar for the IL and IJ, especially for the IL EMIMDCA. Since for BMIMDCA, those properties significantly change upon hydration, the influence of water content [0.4 - 30% (w/w)] was also studied for the ILs. In particular for BMPyrDCA with 30% water, it was analyzed the reorientational polarization by the complex permittivity and electric modulus, from which three different processes were identified: a secondary relaxation with Arrhenian temperature dependence, the process that is believed to be behind the dynamic glass transition and the mobility of charge carriers. An application of the IJs was successfully explored with a chemoresistive gas sensor made up by different IJs as active layer, which is an electronic nose formed by an array of such sensors. The performance of this e-nose revealed its ability to correctly detect eight common volatile solvents

Aerometry instrumentation study Final report

Techniques and instruments for meteorological measurements in Mars and Venus atmosphere